Keri Claussen Khalighi told the L.A. Times the incident happened in 1991, after she met Ratner and Simmons at a casting call in New York.
She claimed they took her to dinner and then back to Simmons' apartment to show her a music video. Khalighi said that is when Simmons allegedly began making aggressive sexual advances.
She said in the article that Simmons took her clothes off and coerced her to perform oral sex all while Ratner "just sat there and watched."
She also claims Simmons penetrated her in the show, hurting her as she jerked away.
MORE: Hollywood harassment scandal widens with accusations against Brett Ratner, Dustin Hoffman
In a statement, Simmons, now 60 years old, strongly disputed her account.
He said, in part: "As a long-time social activist, I have applauded the strength of the brave men and women who have spoken out over the past month and made their voices heard regarding sexual assault and harassment. I am a supporter of the #metoo campaign and the victims who were previously terrified to stand up and speak out against sexual misconduct. I completely and unequivocally deny the horrendous allegations of non-consensual sex against me with every fiber of my being."
Statement of Russell Simmons in Response to LA Times Article. pic.twitter.com/iwT7Wy3SoY— Russell Simmons (@UncleRUSH) November 19, 2017
Actor Terry Crews spoke out against Simmons, too, after Crews talked about his own sexual harassment claims. Last week in an exclusive interview with Good Morning America, Crews opened up about a high-level Hollywood executive grabbing his genitals at a party.
Crews said after he went public, Simmons sent him an email asking for Crews to forgive the executive.
Crews responded on Twitter by posting the email and saying "no one gets a pass."
There was no immediate comment from Ratner about the recent allegations.