The conclusion, contained in an annual report evaluating China's military capabilities, marked another pointed claim by the U.S. government amid rising tensions between the two nations over cyberspace.
The DOD said that last year "numerous computer systems around the world, including those owned by the U.S. government, continued to be targeted for intrusions, some of which appear to be attributable directly to the Chinese government and military. These intrusions were focused on exfiltrating information."
The stolen information is useful to a range of Chinese entities, including its defense and technology industries, U.S. policy makers in China as well as military planners, the report said.
Cyberwarfare capabilities could be used to complicate efforts to respond during a military confrontation, including causing slow response times by constraining the communication and commercial activities of an adversary, the report said.
China has strongly denied that it is coordinating hacking campaigns, but computer security researchers -- as well a major companies such as Google -- have frequently pointed to the nation when describing intrusions.