French prosecutors are investigating rape and sexual assault accusations levelled against legendary actor Gerard Depardieu by a young actress.

A French judicial official said a 22-year-old woman filed a complaint against the 69-year-old near the southern city of Aix-en-Provence this week.

The film star has angrily denied the allegations.

Depardieu’s lawyer Herve Temime said on France’s BFM TV that the actor “absolutely denies any rape, any sexual assault, any crime”.

The investigation was assigned to Paris prosecutors on Thursday (AEST), the judicial official said.

French newspaper Le Parisien and BFM TV said the alleged crimes occurred on August 7 and August 13 this year at one of Mr Depardieu’s Paris residences.

An unnamed comedian and dancer, who reportedly knew the actor before the alleged crimes took place, was “devastated” by the events, her manager was quoted as saying.

Mr Temime said he was convinced his client, who was “shaken” by the allegations, would be exonerated by the end of the investigation.

“I had a long meeting with Gerard Depardieu and I am absolutely convinced his innocence will be established,” he told France Info radio.

He said the accusations go against “everything he (Depardieu) is and respects”.

Depardieu is one of France’s most recognisable actors, having appeared in some 170 films.

He is best known outside of France for his role in the 1990 comedy Green Card, while he also won the best actor award for Cyrano at Cannes and was nominated for an Oscar in the same year.

He previously made headlines for attacking French tax laws and moving to Belgium in protest, and developing close ties to Russian President Vladimir Putin, the BBC reports.

-with AAP