Dale Davidson, 56, was sentenced to life in prison in a Fort McMurray court with no chance of parole for 12 years.
Davidson killed Joyce Walsh, originally from Point May, N.L., in her Fort McMurray home on March 22, 2012.
RCMP say it was not a random attack, but did not release any more details.
Walsh was 49.
Davidson was originally charged with first-degree murder.