The incident allegedly happened back in 2002, according to the gossip website TMZ, who are reporting that the women made an official complaint to authorities on 8 June.
The woman is claiming that she suffered extreme panic attacks after the alleged assault.
But Foxx is denying the incident took place.
“Jamie emphatically denies that this incident ever occurred, and he will be filing a report with the Las Vegas Police Department against the woman for filing a false police report against him," his solicitor Allison Hart said in a statement issues to TMZ.
"The first time [he] became aware of this woman’s absurd claims about an incident that supposedly happened 16 years ago was when TMZ contacted his representatives [on June 12] about the story.
"The alleged incident was not reported to law enforcement in 2002, or at any other time in the last 16 years until last Friday because the incident never happened.”