All 40 people on board a military transport plane were killed when it crashed on Saturday, the state-run Xinhua news agency has reported.
Earlier, unofficial reports had spoken of five casualties.
President Hu Jintao expressed deep condolences over the loss of lives, Xinhua said. He has ordered an investigation into the crash.
The accident happened in the province of Anhui, some 200km (125 miles) south-west of Shanghai.
An unnamed official at the Anhui provincial government office told the Associated Press news agency that the accident had happened at about 1600 (0800 GMT) on Saturday near the village of Yaocun, in Guangde county.
Villagers rushed to the scene after hearing an explosion, a local man told AP by telephone.
The plane's body hit bamboo forest and its tail fell in fields, the man said.
The witness, named only as Tang, said he had seen two bodies before the area was cordoned off.
Details of the type of plane and its flight path have not been given.
Disclosure of military accidents in China is rare.