Hamidi had suffered "cyber-harassment including death, rape and other threats via social media," the prosecutors said.
They added that a specialist online hate unit was investigating.
"I want the terrorists threatening me with death to be identified and tried in court, so that I can live freely without fear and in full safety," Hamidi said in a statement sent to AFP.
The martial artist "has been placed under police protection for an indefinite period," said her lawyers Ines Davau, adding that "we hope the perpetrators of the threats will be swiftly identified".
Hamadi did not manage to qualify for the 2024 Paris Olympics in her under-57 kilogrammes (126 pounds) category. But she has been in the media spotlight in France for "speaking out publicly about women's rights and the Taliban regime," according to her September 3 criminal complaint, seen by AFP.
The document states that the current wave of threats followed her denunciation on social media of an August Taliban law barring women's voices from being heard in public.
Hamidi reiterated her opposition to the law in a press interview and launched the social media hashtag #letusexist.
From the afternoon of September 1, "a vast wave of hatred smashed down on her... her Afghan Whatsapp phone number was shared and she received hundreds of calls and thousands of messages in the space of just a few hours," the complaint read.
Hamidi's criminal complaint specifies the offences of sharing private information, malicious phone calls, death or rape threats, online harassment and online sexual harassment.
