A national lawmaker says sex with underage boys should carry the same penalty as sex with underage girls.
The Criminal Code currently treats sex with boys, whether consensual or not, as child molestation, which is punishable by up to five years in jail.
Sex with a girl under the age of 14, or rape, carries a jail term of up to 10 years, unless severe violence or gang rape is involved.
Zhao Donghua, vice-chairwoman of the China Women's Federation, was quoted as saying the law should be changed to treat the two crimes equally.
Criminal law expert Pi Yijun, of the China University of Criminal Science and Law, said: "The proposal should have been raised a long time ago.
"Chinese society has paid little attention to sexual violence against boys. Neither the general public nor top officials have much knowledge of it, because the conventional idea of heterosexual sex is deeply rooted in Chinese tradition."
Another professor from the same university, Qu Xinjiu, said an amendment was not necessary, as rapes of underage boys were rare compared with those on girls. "Also, rape has long been recognised as a crime against women in the Chinese legal system," Qu said.
But Pi argued the low visibility of sexual violence against boys in the mainstream media did not mean there were fewer incidents.
If a zero-tolerance policy towards underage sex was adopted, more cases involving boys would come to light, he said.
"Many predators, such as those who collect photos of nude boys, do not even realise they are committing a crime," Pi added.
Three CPPCC delegates earlier recommended the crime of "sleeping with young prostitutes" be abolished, saying any man who had sex with underage girls should be charged with rape, mainland media reported.
In 1997, legislators amended the code to introduce the crime of soliciting an underage prostitute.
Legal experts have lobbied for years to have the "underage prostitution" charge dropped, saying it allows powerful officials or businessmen to escape with light sentences for rape.
Without legal protection, underage boy victims cannot sue their attackers for rape.
Pi said a woman judge from Sydney recently told him the loophole had been noticed by potential offenders in Australia.
"She told me there had been Australian travellers to China sexually assaulting Chinese men, as they knew the rape of men was not defined as a crime in China."
In 2010, a 10-year-old boy was found dead in Shaanxi province after he was given narcotics and raped by a male villager, it was reported in 2011.
The victim's family wanted to sue the perpetrator over the homicide. But local prosecutors were quoted as saying: "It's impossible to sue him for rape or charge him with rape."