Peter Debbins is facing life for sharing classified information with Russia military over the course of 10 years.
A DoJ press release says during several visits to Russia in the 2000s he had contact with GRU agents, who knew him by the code name Ikar Lesnikov.
Capt Debbins, 45, faces life imprisonment if convicted.
The Gainesville, Virginia, man is charged with conspiring to provide US national defence information to agents of a foreign government.
“Debbins violated his oath as a US Army officer, betrayed the special forces and endangered our country’s national security by revealing classified information to Russian intelligence officers, providing details of his unit, and identifying special forces team members for Russian intelligence to try to recruit as a spy,” Assistant Attorney General John Demers said.
“Our country put its highest trust in this defendant, and he took that trust and weaponised it against the United States.”