On a farm in Beijing with 9,835 pigs, 85 pigs were confirmed infected with the viral disease and 17 confirmed dead, the ministry said, citing a China Animal Disease Control Center report.
Outbreaks were also found in the provinces of Shaanxi and Heilongjiang, where at least 156 pigs have been confirmed dead, it said.
Local authorities have initiated an emergency response to block, cull and disinfect the affected pigs.
The ministry also lifted quarantine in a city in northeast China's Liaoning province after assessment, where an African swine fever outbreak occurred in October.
The ministry has demanded local governments step up monitoring and take active measures to prevent recurrence of the disease.