The decision by Dan Church, who was named the head coach of Canada's national team in June 2012, is a bombshell for a squad that is seeking a fourth consecutive Olympic gold medal.
"I have understood from the beginning of this process that winning gold in Sochi was this team's only focus," Church said. "I believe that stepping aside for personal reasons at this time will help the team achieve its goal."
Church helped lead Canada to a gold medal at the 2012 world championships before losing to the United States in the final of this year's tournament.
Hockey Canada said assistant coaches Danielle Goyette and Lisa Haley will be interim co-coaches for the immediate future.
Canada's team for the February 7-23 Olympics was expected to be announced before the end of December.