The outbreak occurred on July 14 in a community in Xinjiang Uygur Autonomous Region's Aksu city, and the H5N1 virus was found in the samples of the dead poultry by the national bird flu laboratory, the Ministry of Agriculture said.
The H5N1 strain of avian flu had killed 3,045 chickens, and another 356,976 had been culled in an emergency response.
The local agricultural department has quarantined the infected area and the outbreak is now under control, the ministry claimed.
China is currently one of the worst-hit countries from bird flu. It has reported over 35 cases of bird flu in poultry, resulting in the culling of over 25 million poultry.
The country reported its first human bird flu case in November, 2005. Since then, it has reported 19 cases of bird flu infections in humans out of which 12 died.