Police officials said a 50-year old actress filed a report claiming the actor assaulted her in the 1990s at his Santa Monica office.
The Los Angeles District Attorney's Office is reviewing sexual assault allegations against Sylvester Stallone, according to a DA spokesperson.
The Santa Monica police department said in December it was investigating a report of alleged sexual misconduct by Stallone.
Reps for Stallone did not immediately respond to Fox News' request for comment.
Stallone's lawyer, Marty Singe, has denied any wrongdoing by his client and says the investigation should not have been made public. The Daily Mail in November reported that it had obtained a police report alleging that Stallone forced a 16-year-old girl into a threesome with himself and his bodyguard, Mike De Luca, at a Las Vegas hotel.
"It is under review by our sex crime task force".
In other cases against Hollywood figures, the DA in Los Angeles has thus far declined to file criminal charges. Any crimes committed out of that time frame can not be prosecuted in California.
Stallone skyrocketed to fame in 1976 with his Oscar-winning boxing film Rocky and went on to become one of Hollywood's biggest action stars.
In 2016, California ended the statute of limitations on some sex crimes, including rape, forcible sodomy and molestation of a child.
Singer said Stallone "categorically" disputed the claim at the time.
"It wasn't until after the #MeToo movement began making headlines a year ago - following the Harvey Weinstein scandal - that she surfaced with the allegations", Singer said. The stories resurfaced in November 2017 after those outlets got access to police case files.