The outbreaks of the virulent H5N1 virus in Liaoning's Jinzhou city and Fuxin city began on Sunday and were confirmed Wednesday, according to a report by the Ministry of Agriculture posted on the Web site of the World Organization for Animal Health.
The report identified the source of infection as "wild animals," presumably migratory birds.
The news came a day after Chinese Premier Wen Jiabao, while inspecting Liaoning's flu prevention work, warned that the country faces a serious threat from bird flu, since the disease is still not under control despite massive nationwide efforts to stop its spread.
The government has ordered increasingly strict preventive measures.
China hasn't reported any infections in humans by the H5N1 virus, which has killed at least 63 people elsewhere in Asia. But health officials say cases are inevitable if China can't stop repeated outbreaks in poultry.
Authorities fear that H5N1 could mutate into a form that is easily passed from human to human, sparking a possible pandemic, AP reports.