Published at 7:15 p.m. ET --
Sub-Lt. Jeffrey Delisle, dressed in a blue hooded sweatshirt and jeans, showed no reaction when found guilty of breach of trust and handing information to a foreign entity that could harm national interests.
He was also fined $111,817 (Canadian), the sum he received from his Russian spy masters.
Delisle, 41, worked at a security unit in Halifax that tracked vessels entering and exiting Canadian waters. He stole secret information by copying it onto a computer memory stick.
Officials told a sentencing hearing last week that allies had threatened to withhold intelligence from Canada unless it tightened security procedures.
Canada shares sensitive information with the United States, Britain, New Zealand and Australia.
Gen. Tom Lawson, chief of the Canadian defense staff, said Canada was boosting security in the wake of what he called Delisle's odious behavior.
"A critical foundation of our intelligence mission is the mutual trust we have forged with our allies ... Sub-Lieutenant Delisle failed each and every Canadian," he said in a statement.
Delisle, unhappy after his marriage started to break up, walked into the Russian embassy in Ottawa in July 2007 and offered to sell secrets.
Authorities first became suspicious after Delisle returned to Canada from a meeting with a Russian handler in Brazil in 2011, carrying tens of thousands of dollars in cash and pre-paid credit cards. This prompted an investigation that ended with the officer's arrest in January 2012.
He was the first person to be charged under a secrecy law that was enacted after the attacks of Sept. 11, 2001, and can carry a life sentence. Prosecutors had demanded a 20-year sentence while Delisle's lawyers argued a 10-year term would be appropriate.
As he left court he glanced briefly at several members of his family in the room.
Defence lawyer Mike Taylor said Delisle "is a little bit shocked. It's a significant sentence that he received and one that quite frankly I don't think he was really expecting."
Taylor told reporters it was too early to say whether an appeal would be lodged.
Delisle was also given nine years in jail for attempting to communicate information to a foreign entity and five years for breach of trust, with all sentences to be served concurrently.
Taking the time he served in pretrial custody into account, Delisle will spend 18 years and five months in jail.
