Two netizens, surnamed Li and Cai, are being detained for five days for spreading false information as no H7N9 cases have been reported in the province, according to the public security bureau of Guiyang, the provincial capital.
They wrote on their microblogs Monday that "sample tests were positive for the H7N9 virus in Jinyang live poultry market in Guiyang."
Many netizens reposted the message online, state run Xinhua news agency reported.
Another netizen, surnamed Gong, actively participated in spreading the rumour, which caused fear among some netizens and local people.
Nine people have been killed in China due to new bird flu strain.