The CSA watchdog has received 39,200 complaints about the stunt, in which presenter Cyril Hanouna broadcast phone calls to people who had answered an online dating ad he had placed.
Most of the people he called were gay men and the CSA found that he had repeatedly "resorted to numerous clichés and stereotypes about homosexual people".
In broadcasting the sequence, the TV channel C8 had "seriously ignored the principle of respect of privacy, as well as the obligation to combat discrimination", the CSA judgement said.
But it did not accept the examining magistrate's recommendation to suspend Hanouna's broadcast, Touche pas à mon poste (Don't touch my set), for a week.
Channel claims discrimination
Accusing the body of "inequitable and discriminatory treatment", C8 says it will appeal against the fine.
"Well darlings the most important thing is that we will be on air on 1 September for a new, wild season," Hanouna tweeted.
Gay rights campaigner Joël Deumier hailed a "historic decision", claiming that they fact that the sanction hits the broadcaster "in the wallet" means that "you can no longer humiliate homosexuals on TV and radio today".
The fine is one of the heaviest ever imposed by CSA.
The CSA has examined 16 cases relating to Hanouna's programme, deciding to take no action on four of them.
In June it stopped advertising during the show for three weeks for sexism and failure to respect personal dignity.