Ralph Mariano also pleaded guilty to theft of government property and tax evasion on Thursday after his girlfriend, Mary O'Rourke, pleaded guilty to theft of government property in the same case.
Prosecutors say Mariano used his position at the Naval Undersea Warfare Center to add money to contracts held by corrupt contractors, who then funneled money back to Mariano and others.
Outside court, Mariano and his lawyer had no comment. O'Rourke's lawyer said his client is relieved that it's over.
Mariano and O'Rourke are scheduled for sentencing Sept. 5.
All six people charged in the case have now pleaded guilty.
Copyright 2013 The Associated Press.