The actor and comedian is not disputing that he had a sexual encounter with an anonymous accuser, but insisted that it was "completely consensual".
The claims, published on Sunday in online magazine Babe, were made by a 23-year-old photographer from New York.
She had met Ansari (above), 34 - who recently won a Golden Globe for his performance in Netflix comedy Master Of None - in September last year at the Emmy Awards' after-party.
They met for dinner in New York about a week later. They proceeded to his apartment, where she said he made repeated aggressive advances towards her.
That was despite her "verbal and non-verbal cues" indicating she did not want to have sex.
"I believe that I was taken advantage of by Aziz. I was not listened to and ignored. It was by far the worst experience with a man I've ever had," she told Babe.
In a statement in response, Ansari told Babe: "We went out to dinner and, afterwards, we ended up engaging in sexual activity, which by all indications, was completely consensual.
"The next day, I got a text from her saying that although 'it may have seemed okay', upon further reflection, she felt uncomfortable.
"I took her words to heart and responded privately after taking the time to process what she had said."
Ansari is known for his roles as Tom Haverford in sitcom Parks And Recreation and Dev Shah in Master Of None, for which he is also a writer.
JOEL KRAMER Two veteran stuntwomen have directed allegations of sexual misdeeds against the well-known stunt coordinator.
The claims come after actress Eliza Dushku had accused him over the weekend of sexually molesting her during the making of 1994 movie True Lies when she was 12.
Kramer, 60, who, for many years, was Arnold Schwarzenegger's personal stunt double, has denied Dushku's allegations.
But he did not counter a claim by Laura Albert, one of the two stuntwomen, that he had a sexual encounter with a 16-year-old. The latter had accompanied Albert's younger sister to the location shoot in North Carolina of science-fiction movie Virus in 1997.
The police were informed, but their hands were tied, as the age of consent in that American state is 16.
The other stuntwoman, who wanted to remain anonymous, claimed that Kramer sexually assaulted her in his car in the late 1970s or early 1980s.
Meanwhile, Schwarzenegger, who starred in True Lies, has tweeted that he is "shocked and saddened for Eliza, but I am also proud of her... she is so courageous".