Rebel Wilson says she’s dealing with multiple lawsuits … and now she’s firing back at the man she says is funding them — calling him out for being mentioned in the Epstein Files.

Rebel went OFF in a series of posts on her Instagram Stories, slamming billionaire Sir Len Blavatnik, alleging he neglected to help her when she called out what she deemed to be bad behavior on set.

Remember … Gregor Cameron, Vince Holden, and Amanda Ghost — producers on Rebel’s directorial debut “The Deb” — filed a defamation lawsuit against Rebel after she claimed they embezzled $900,000 from the film’s budget and said Ghost sexually harassed the film’s lead actress, Charlotte MacInnes.

Now, Rebel says she flew to New York and asked Blavatnik for help with “the struggles I had with the people that worked for him: Amanda Ghost, Gregor Cameron, and Vince Holden,” and she “sincerely thought he would do something about it.”

She claims he instead used his money to fund “four lawsuits across two continents against me.”

Rebel says she also saw his name pop up in the Epstein Files … sharing an email which appears to show Jeffrey Epstein asking someone to reach out to Blavatnik to give one of Epstein’s friends a job.

Bottom line … this fight is getting nastier by the minute, so stay tuned!