The state's highest court found the judge at the trial prejudiced the ex-movie mogul with "egregious" improper rulings, including a decision to let women testify about allegations that weren't part of the case.
In a 4-3 decision, the ruling by the Court of Appeals will mean a painful chapter in reckoning with sexual misconduct by powerful figures looks likely to be reopened.
It was an era that began in 2017 with a flood of allegations against Weinstein dating back to the 1970s.
Weinstein's accusers could again be forced to relive their traumas on the witness stand.
The 72-year-old former film producer has been serving a 23-year sentence in a New York prison for sexually assaulting ex-production assistant Mimi Haleyi in 2006 and raping former aspiring actress Jessica Mann in 2013 following the landmark 2020 trial.
However, he will remain behind bars as he was sentenced last year in Los Angeles to 16 years in prison for raping and sexually assaulting an actress in a Beverly Hills Hotel.
The Los Angeles conviction is not affected by today's decision in New York.
Manhattan district attorney Alvin Bragg - who is already involved in a hush money trial against former president Donald Trump - will now decide whether Weinstein will receive a retrial.
A spokesperson for Mr Bragg said in an email: "We will do everything in our power to retry this case, and remain steadfast in our commitment to survivors of sexual assault."
Douglas Wigdor, a lawyer who represented eight of Weinstein's accusers said today's decision was a "major step back in holding those accountable for acts of sexual violence," adding: "It will require the victims to endure yet another trial."
Once considered the most powerful man in Hollywood, Weinstein was accused by dozens of women claiming he bullied, pressured, coerced, or overpowered them while demanding sexual favours.
Gwyneth Paltrow, Salma Hayek, Lupita Nyong'o and Ashley Judd were some who accused Weinstein of sexual harassment, while actresses Asia Argento and Rose McGowan were among others who accused him of raping them.
He was also accused of reaching settlements to keep the stories quiet.
Weinstein had admitted his behaviour had "caused a lot of pain", but maintains his innocence throughout saying any sexual activity was consensual.
The glut of allegations sparked #Metoo, a movement where alleged victims of sexual assault increasingly publicised their experiences, and many came forward against high-profile figures, especially in the entertainment industry.
Weinstein co-founded the entertainment company Miramax in 1979 whose hit movies included Pulp Fiction, Flirting with Disaster and Shakespeare in Love.
He was ousted from his own firm, The Weinstein Company, in 2017 after the New York Times reported nearly 30 years of rape and sexual harassment allegations towards him.
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The house has been put on the market less than three months after an unauthorised spa pool block in the grounds of the Grade II-listed property was knocked down by order of planning bosses.
The Old Rectory in Marston Moretaine in Bedfordshire is described as a "magnificent seven-bedroom property" by estate agents Fine & Country.
A video tour of the house shows a sculpture of the retired Army officer with his walking frame and a photograph of him being knighted by the late Queen in 2020.
Introducing the property, an estate agent says in the tour video: "I'm sure you'll recognise this iconic and very famous driveway behind me as it was home to the late Captain Sir Tom Moore who walked 100 laps of his garden raising over £37m for NHS charities."
In August 2021, the fundraising hero's daughter Hannah Ingram-Moore and her husband were granted permission to build a Captain Tom Foundation Building at the property.
The couple used the Captain Tom Foundation name on the first set of plans.
However, the foundation's name was not used on a subsequent retrospective application for a larger building containing a spa pool, which was refused by the planning authority in November last year. At the time, the block was partially built.
The organisation, which was founded in June 2020 in honour of Sir Tom, is currently being investigated by the Charity Commission.
The investigation is not connected to the £38.9m, including gift aid, which Sir Tom raised for the NHS.
Sir Tom became a national hero by walking 100 laps of his garden before his 100th birthday at the height of the country's first national COVID lockdown in April 2020.
He was personally knighted by Queen Elizabeth II for his efforts during a unique open-air ceremony at Windsor Castle that summer.
He died in February 2021 - weeks before his 101st birthday.
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The 18th-century home boasts four bathrooms, four reception rooms and is set within 3.5 acres (14,200 square metres) of land, with a standalone coach house.
Anyone interested in buying it will have to prove they can afford it, the listing says.

The actor-turned-politician was successfully sued by former Stonewall trustee Simon Blake and drag artist Crystal over a row on X.
After losing a High Court libel battle, it means he will have to pay out £90,000 to each of them.
Fox called Mr Blake and Crystal, a former RuPaul's Drag Race contestant whose real name is Colin Seymour, "paedophiles" in an exchange they had over Sainsbury's decision to mark Black History Month in October 2020.
The Reclaim Party founder said at the time he would boycott the supermarket and he attempted to counter-sue the pair, along with broadcaster Nicola Thorp, over tweets accusing him of racism.
In a previous judgement in January, Mrs Justice Collins Rice dismissed Fox's counter-claims and ruled in favour of Mr Blake and Mr Seymour.
In today's ruling, the judge said Fox should pay out £180,000.
"By calling Mr Blake and Mr Seymour paedophiles, Mr Fox subjected them to a wholly undeserved public ordeal," the judge said.
"It was a gross, groundless and indefensible libel, with distressing and harmful real-world consequences for them."
The judge added: "There is no element of punishing Mr Fox in that; it is a purely compensatory award to redress the damage done and restore the equilibrium that his libels violated, and which he has not taken the opportunity to restore more fully himself.
"Mr Blake and Mr Seymour have been successful in fighting for their legal rights and are entitled to the law's effective vindication.
"They have also been resilient and resourceful in trying to get on with the rest of their lives and have had strong support at home, in the workplace and in some quarters of the public and media to help them do so.
"Had that not been so, and Mr Fox's random selection of victims turned out to be less self-sufficient and well-supported individuals, this award would have had to have been considerably higher."
Fox was also ordered not to repeat the same, or similar allegations, on pain of being found guilty of contempt of court.
The judge also accepted evidence from Mr Blake and Mr Seymour that they experienced Fox's libel as "distinctly homophobic".
At a hearing in March, Lorna Skinner KC, for Mr Blake and Mr Seymour, argued the pair should receive "at least six-figure sums" from Fox.
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However, Patrick Green KC, for Fox, said the starting point of the damages should be between £10,000 and £20,000, with the total being "substantially lowered" due to an apology from Fox and the alleged absence of malice.
Ahead of Thursday's ruling, Fox claimed the judgement was a "bullies' charter". He added: "Enjoy the victory guys and I hope it is short lived!"
In the aftermath, he posted on X, saying the judgement was: "So surreal it's almost funny."
He added: "Will be appealing."
The judge declined to make an order forcing Fox to publish a summary of the ruling on his X account, where he has almost half a million followers.
During the hearing in March, Mr Green said that there was no need to publicise the ruling on Fox's social media because "this has been the most high-profile libel action of the year".
Mr Green added: "The remarks were quickly retracted and apologised for, and at the very least it was clear to the public at large at an early stage that the allegation was baseless."

Ahmed Ali Alid, 45, attempted to kill his housemate, a Christian convert, stabbing him in his bed as he slept.
He then prowled the streets of Hartlepool until he came across Terence Carney, 70, who was out for a morning walk, attacking him and stabbing him to death.
He told police the attack, a week after the Hamas attacks on Israel, was "for the people of Gaza" and he had wanted to kill more victims.
At the end of his police interview, Alid attacked two female officers, yelling "Palestine" and "Allahu Akbar" - meaning "God is great" - as he grabbed one of them and wrestled her to the ground, causing his solicitor to dial 999.
The court heard Alid, a former pastry chef, had travelled from Morocco to Spain in 2007 and spent time in 13 different European countries before arriving in Britain.
He spent 13 years living in Italy, Germany - where he was denied asylum - and Spain, before arriving in Middlesborough by ferry from the Netherlands in 2020.
He claimed asylum and spent the next three years living in a hotel in Hull and then state-funded accommodation in a terraced house in Hartlepool, waiting for his claim to be processed.
'Watching terrorist news'
Alid's housemate had alerted police that he was an "extreme Muslim" and said that he would sit in the kitchen with a knife and give him "bad looks" after realising he had converted to Christianity.
Javid Nouri, an Iranian asylum seeker, described how he found Alid laughing and "watching terrorist news" on his phone in the kitchen following the 7 October attacks by Hamas.
Nouri told the managers of the hostel he believed Alid was a "terrorist" and went to police on 13 October, but was told there was nothing they could do unless Alid was carrying the knife around the house or using it to threaten his housemates.
Two days later, Nouri was woken around 5am when Alid broke into his bedroom, brandishing two kitchen knives and stabbed him in the chest.
Nouri, a former bodybuilder, described Alid shouting "Allahu Akbar".
He managed to kick Alid away and run for the door but was then attacked from behind and stabbed in the face, before grappling with Alid and getting him into a headlock.
One of his housemates, another Christian convert from Iran, helped bundle Alid out of the room and sat with their backs against the door as Alid kicked at it, attempting to get back in.
However, one of the knives had ended up in the corridor and Alid picked it up and went out on to the street where he passed Terrence Carney, circling back and approaching him from behind.
CCTV showed him stab Carney a number of times while his victim was "effectively defenceless" and crying out "no, no," Jonathan Sandiford KC, prosecuting, told the court.
Armed police caught up with Alid nearby and he was arrested.
As he was taken to the police station on suspicion of terrorism offences, Alid was shown on bodyworn footage talking in Arabic, translated for the jury, in which he said: "For the people of Gaza inshallah [god willing].
"Inshallah Gaza will return to our country. I am Arab, I am Arab, I am Arab, it will return to Arab country. I am the son of Arabs, in the name of Allah."
'My intention was to kill more'
During his police interview, Alid, a fitness fanatic and fan of mixed martial arts, told the officers through an Arabic translator: "The whole issue is for the independence of Palestine. To have two dead victims is better than more.
"It is between the Zionist entity and Hamas movement. They set a specific time for shooting and if this Zionist occupation does not leave, here in Britain there will be [a] flood, unrest."
Asked if he intended to kill more people, Alid said: "I swear by Allah if I had a machine gun and I had more weapons that they would be in thousands.
"I was going to contact someone to get me a machine gun and I would have done more and then that person told me to carry on with the knife."
He told the officers if it had not been for the wounds to his hands from the knife, he would have continued the killing.
"There would have been more lives. My intention was to kill more people, not only him," he added, referring to Mr Carney.
In court, Alid withdrew his confession and claimed he had acted in self-defence after going into Nouri's room to confront him about arguments in the house and getting attacked himself.
He claimed that he had then walked the streets shouting "free Palestine!" in a "loud voice" when he came across Mr Carney who told him to "go back to your country and stay there".
The jury rejected his claim and found him guilty of murder.
In a statement, Mr Carney's family said: "We would not want anyone else to have to go through what we have had to go through over the last six months, and what we will continue to go through for the rest of our lives. For us, things will never be the same again.
"We have watched the whole trial intently, and whilst today's guilty verdict will not bring back Terence our beloved husband, father, and grandfather, we can take some small comfort in knowing that justice has been served."
Rejected asylum claim
Alid, who said he left Morocco in 2007 after having a "problem" with the intelligence services, spent time in 13 different European countries before arriving in Britain.
Alid first arrived in Cadiz, Spain in 2007, and then travelled to France, Italy and Greece before returning to Italy where he lived and worked for nine months.
From Italy, he moved to Germany, where he lived between 2009 and 2011. He applied for asylum in Germany and was refused.
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After his release, he travelled to Denmark, Sweden, Norway and Finland, where he stayed for two months, hoping to set up a shop with someone from Somalia, but he was deported back to Germany.
He travelled to Switzerland and Vienna in Austria before eventually returning to Germany, where he lived between 2014 and 2018.
He then spent two years in Spain, before entering Britain illegally via a ferry in 2020.
He was arrested by the police during the COVID pandemic and told them he did not have any documents, resulting in him lodging a claim for asylum.
Alid was initially housed in a hotel in Hull before he was sent to "dispersal" lodgings in Wharton Terrace, Hartlepool.
Asked if he had been successful in applying for asylum during the three years he spent in Hartlepool, he said: "I didn't get any answer."

The Household Cavalry said the animals - which were taking part in what the Army called a "routine exercise" in the Belgravia area on Wednesday - were spooked by builders dropping rubble from a height "right next to them".
In a statement on X, the Army said one of the horses which had been operated on had been taken to an equine hospital.
The other affected horses are being closely observed.
It added: "Our horses receive the highest standards of care, and those that did not undergo surgery are expected to return to duty in due course.
"We want to thank everyone who has shown such kindness and concern towards our soldiers and horses. We will provide more updates soon."
Defence minister James Cartlidge told Sky News this morning: "There were five horses. They have all been recovered.
"Three of them are fine, two of them are unfortunately in a relatively serious condition and obviously we will be monitoring that condition."
He added: "They are in a serious condition, but as I understand, still alive."
Sky News understands the horses in a serious condition are named Vida - the lighter horse - and Trojan (the darker horse).
The other two that ran loose were called Quaker and Tennyson.
He stressed while the footage that emerged of the horses running through the capital was "dramatic", it was "a very exceptional event".
"This is extremely unlikely, this scenario," he told LBC.
"Unfortunately we have seen what has happened, but all I can say is the crucial thing... no serious injuries to the public as far as we aware, and of course we will be keeping an eye on the situation."
Four service personnel were thrown from their horses and the animals that ran loose smashed into vehicles, including a taxi and a tour bus.
Paramedics treated four people in three separate incidents in Buckingham Palace Road, Belgrave Square, and at the junction of Chancery Lane and Fleet Street, in the space of just 10 minutes.
Some of the soldiers were taken to hospital for treatment for their injuries, which were not thought to be serious.
The Army said three soldiers who were injured would "recover fully and return to duty".
One witness got off a bus and described seeing two horses, one black and the other white, "flying past".
"The white one was drenched in blood from the chest down and they were galloping through the traffic at speed," she said.
"People were stopping in the street shocked. The horses were running into fast-moving traffic and seemed terrified. Some unmarked police cars were chasing after them, which didn't seem to be helping.
"I felt shocked. It was pretty gruesome. Felt like a weird dream."
The horses were eventually recaptured by City of London Police and taken away to be assessed by Army vets.
The animals are all receiving care from vets at Hyde Park barracks.
Commanding Officer of the Household Cavalry Mounted Regiment Lieutenant Colonel Matt Woodward said in a video statement posted on X the unit exercises around 150 horses on the roads and in parks every morning, partly to help desensitise them to city noise.
He said the "shock" of building materials being dropped from a height near them caused the horses to bolt and unseat some riders
He added: "Thankfully, considering the frequency of exercise and numbers of horses involved, this type of incident is extremely rare, we continue to strive to minimise the risk of this recurring.
"As ever we are grateful for due consideration given by the members of the public to not making loud noises around our horses."