The gay male population has been hit particularly hard, accounting for more than 25 percent of the total.
Wu Zunyou, head of the National Center for AIDS/STD Control and Prevention, made the remarks on the sidelines of the ongoing 2015 National Conference on HIV/AIDS.
"The situation among gay men is alarming and in some cities one out of five gay men is HIV positive," he said, citing a national average of 8 percent among the group.
In worse-hit cities such as Beijing and Harbin, more than 70 percent of the cases reported in 2015 involved gay men, he added.
Worse, young students have been hit hard in recent years by the epidemic, he said, and 70 to 80 percent of the HIV/AIDS cases detected in 2015 among them involved gay sex.
"It's a big challenge to protect young students from HIV/AIDS," he said.
Thanks to robust intervention efforts initiated in 2003, China has a low prevalence of HIV/AIDS (0.06 percent), according to Shen Jie, deputy director of the Chinese Association of STD and AIDS Prevention and Control, which hosted the conference.
"But the rapid increase of HIV cases among gay men has hardly been curbed," she said.
Mainstream prevention strategies like education and behavioral intervention didn't work well for them, said Wu.
Condom use, for instance, has never exceeded 50 percent of the gay male population, he noted, citing previous investigations.
"I even saw a gay medical doctor who had unprotected gay sex," he said.
Many of them are aware of the risks and preventive measures like condoms and lubricant use but simply don't practice accordingly, he pointed out.
Wu suggested that improved treatment should be the best way to help curb the quick spread of the virus among gay men.
HIV/AIDS sufferers are much less likely to pass the virus to others if put on antiretroviral therapy, he explained.
In that regard, "treatment is prevention," he said.
shanjuan@chinadaily.com.cn