The Marseille-based Didier Raoult is accused in the complaint by medical peers of spreading false information about the benefits of hydroxychloroquine.
US and Brazilian presidents Donald Trump and Jair Bolsonaro seized upon Raoult's promotion of hydroxychloroquine and have trumpeted its benefits since the pandemic erupted.
But the method and conclusions of Raoult's studies were challenged from the start by critics and other scientists who said they had not been peer reviewed and were observational, not controlled.
A group representing 500 specialists of France's Infectious Diseases Society (SPILF) filed a complaint with the national Order of Doctors against Raoult in July, accusing him of breaking nine rules of the doctors' code of ethics, French newspaper Le Figaro said on Wednesday.
A spokeswoman for the association told AFP that the complaint had been filed but said it would not make any further comment while the procedure was in progress.
Raoult, who heads the infectious diseases department of La Timone hospital in Marseille, said in March that his study of 80 patients showed “favourable” outcomes for four in five of those treated with hydroxychloroquine.
But the six-page complaint, seen by Le Figaro, slammed the promotion of the drug “without any real scientific evidence on the subject, and against the health authorities' recommendations”.
“We can ask ourselves whether his unequivocal points of view… harmed public health recommendations,” the complaint added.
Raoult risks sanctions ranging from a warning to a ban on practising.
French President Emmanuel Macron visited the colourful scientist with shoulder-length blond hair and a grey beard on April 9th at the height of the pandemic, when the French were observing strict stay-at-home rules.
Contacted by AFP, La Timone's infectious diseases department declined to comment.