Kevin Mallory, 62, was found guilty of several spying offences following a two-week trial in June 2018 and sentenced by a federal judge in Northern Virginia on Friday, the New York Times reported.
Prosecutors said that he provided a Chinese intelligence officer with classified documents, a violation of the Espionage Act.
The fluent Mandarin speaker from Leesburg, Virginia, held top-level security clearance and had access to sensitive documents. He was convicted of selling secrets to China for $25,000.
Evidence at his trial included a surveillance video which showed him scanning classified documents onto a digital memory card at a post office. He also travelled to Shanghai to meet a Chinese agent in March and April 2017, the US Justice Department said.
"Mallory not only put our country at great risk, but he endangered the lives of specific human assets who put their own safety at risk for our national defence," said G. Zachary Terwilliger, US Attorney for the Eastern District of Virginia.
"This case should send a message to anyone considering violating the public's trust and compromising our national security. We will remain steadfast and dogged in pursuit of these challenging but critical national security cases," added the attorney.
The Justice Department said Mallory held a number of sensitive jobs with government agencies. He had worked as a covert case officer for the Central Intelligence Agency and as an intelligence officer for the Defence intelligence Agency (DIA).
"This case is one in an alarming trend of former US intelligence officers being targeted by China and betraying their country and colleagues," said Assistant Attorney General John Demers following the sentencing.
Earlier this month, former CIA agent Jerry Chun Shing Lee pleaded guilty to spying for China. Prosecutors said the naturalized American citizen was paid to divulge information on US covert assets.
Last June, former US intelligence officer Ron Rockwell Hansen was also charged with attempting to spy for China.