China has appointed a new air force chief and reshuffled other top military leaders ahead of the ruling Communist Party's once-in-a-decade leadership transition next month, state media said.

Ma Xiaotian, an army general who has taken part in military exchanges with countries including the United States, has been promoted to commander of China's air force, several state-run websites said, citing Chinese financial news service Caixin.

He replaced Xu Qiliang, another general who has been tipped to become vice-chairman of China's Central Military Commission, which governs the armed forces.

Wang Guanzhong, formerly head of the Central Military Commission's general office, has taken Ma's previous post as deputy chief of staff for China's People's Liberation Army, the reports said.

Other promotions detailed in the reports include the appointment of Zhu Fuxi as military chief in the southwestern Chengdu military zone, which includes most of Tibet.

China has increased investment in its 2.3-million-strong army as part of a modernisation drive, previously saying that military spending would top $100 billion in 2012, up 11.2 percent from last year.

The reshuffle comes ahead of the ruling Communist Party's pivotal congress next month, which will see the announcement of a new crop of leaders for the next 10 years.

Top military figures are thought to have influenced internal party debates over the selection of the new leadership.