The 16-year-old girl filed the report with Las Vegas police, alleging that Stallone and his bodyguard Michael 'Mike' De Luca 'intimidated' her into having sex at a hotel in 1986.
The explosive documents were first obtained by DailyMail, who have claimed the teenager said she had sex with Stallone and he asked De Luca to join them. The girl reportedly became 'very uncomfortable' with the situation but felt she had 'no choice'.
De Luca then forced the teenager to perform oral sex on him before having sex with her, while Stallone made her give him oral sex, according to the police report.
Retired Las Vegas metro police department detective sergeant John Samolovitch, who was head of the sexual assault unit at the time, confirmed the allegations to DailyMail, saying: 'The copy of the police report is in fact a true copy of the original report.'
After the incident, the teenager claimed to have been threatened by Stallone and De Luca who allegedly said 'they would beat her head in' if she told anyone.
Stallone is yet to comment on the allegations.