BEIJING — China has banned television and radio ads for push-up bras, figure-enhancing underwear, and sex toys in the communist government’s latest move to purge the nation’s airwaves of what it calls social pollution.

Regulators have already targeted ads using crude or suggestive language, behavior, and images, tightening their grip on television and radio a few weeks ahead of a twice-a-decade Communist Party congress at which some new senior leaders will be appointed. The latest move by the State Administration of Radio, Film, and Television, or SARFT, also bans ads for sexual aids that claim to boost performance in bed.

“Illegal ‘sexual medication’ advertisements and other harmful ads pose a grave threat to society,” said the SARFT notice, issued in the past week and posted on the administration’s Web site.

“They not only seriously mislead consumers, harm the people’s health, pollute the social environment, and corrupt social mores, but also directly harm the credibility of public broadcasting and affect the image of the Communist Party and the government,” the notice said.