The athletes who tested positive, includes a top women's marathon runner Wang Jiali, thus becoming the first Chinese to fail the biological passport program.
Former Beijing Marathon winner and National champion Jiali has been suspended since February after anomalies were discovered in her biological passport, which recorded data from her blood samples collected between May 2012 and January 2013.
The 27-year-old has never tested positive in anti-doping tests before, a report by state run Xinhua news agency said. China introduced the new anti-doping scheme in 2012. By far there have been 12 doping cases this year, leveling with the last year's total.
China's Anti-Doping Agency (CHINADA) said the rise in number of positive cases may have something to do with the approaching Chinese National Games.
"The number of positive cases has largely increased compared with that of last year, which sent us a warning," CHINADA head He Zhenwen said. "There always will be someone who risks doping for unfair advantage when the return is lucrative.
History taught us that the National Games could well be the reason for cheating," he was quoted as saying by Xinhua. The National Games, inaugurated in 1959, originally with an aim to promote sport and encourage the mass public to build up their bodies, drew teams representing provinces, municipalities and autonomous region.
The National Games program includes most Olympic sports. Good results at the Games are viewed as work achievements of provincial sport bureaus and usually bring medal winners even higher rewards than international titles do. This year's National Games will be held in northern province Liaoning from August 31 to September 12.