Both Stallone and bodyguard Michael De Luca allegedly sexually assaulted the teenager at the former Las Vegas Hilton hotel during the filming of Over the Top.
The girl met Stallone (then 40) in the hotel arcade and initially approached him for an autograph.
She says she consented to having sex with Stallone in his hotel room (16 is the age of consent in Nevada), but when she got there was forced to perform oral sex on both men.
According to the report, De Luca also proceeded to have sex with the teen without her consent.
The teen claimed Stallone threatened to “beat her head in” if she reported the incident.
She told police that she felt “uncomfortable” and “intimidated” by the men and by De Luca's presence.
In a statement made to TMZ, Stallone denied the claims made against him and the late De Luca (who died in 2013)
“This is a ridiculous, categorically false story. No one was ever aware of this story until it was published today, including Mr. Stallone. At no time was Mr. Stallone ever contacted by authorities or anyone else regarding this matter. It never happened.”