The man, identified only by his surname Xiang, was detained following the Friday event in the city of Changsha and ordered to serve 12 days in a detention center for organizing an illegal march, according to a notice on the local police's microblog account.
Changsha newspaper Xiaoxiang Morning News quoted Xiang as saying before the march that he hoped it would make people question discrimination against gays, lesbians, bisexuals and transgender people, and "let more people have a correct understanding of us."
China requires prior police approval for all marches and street demonstrations and permission is rarely granted. Reports said about 80 people took part in the march along a riverfront park, carrying anti-discrimination banners and a giant rainbow flag, and there was no mention of problems with police at the time.
Xiang's detention underscores the limits the conservative Communist government continues to impose on campaigners as it seeks to contain demands for more free expression and civil rights. Police enjoy broad powers to monitor, harass and detain activists for causes ranging from religious rights to the environment. Those caught in the system have little legal recourse, although some whose cases have raised a public outcry have been released.
Activists find greater room for expression on the Internet, despite heavy censorship, and organizers of the Changsha march maintained a website, rt1069.com. They stated their hope that the march would "write a new chapter in the struggle for equal rights for comrades," using the Chinese slang term for homosexual.
The march was the second held in Changsha on May 17, International Day Against Homophobia, and was joined by similar events in several other Chinese cities.
Chinese society is increasingly accepting of gays and lesbians, although same-sex partnerships are not recognized and no laws outlaw discrimination against sexual minorities. A law against "hooliganism" used to target gays was eliminated in 1997 and homosexuality removed from the list of mental disorders in 2001.