His appointment was announced Wednesday at a news conference at the Hockey Hall of Fame in Toronto held by Bob Nicholson, president and chief executive officer of Hockey Canada.
Messier, a 25-year NHL veteran, currently is a special assistant to the president and general manager of the New York Rangers.
"I am excited to be working with Hockey Canada in preparing for the 2010 World Championship in Germany," Messier said.
"With his tremendous hockey background and his great leadership skills, we feel that Mark will be a great general manager for us as we strive to get Canada back on the top of the podium in Germany," Nicholson said.
Messier played teams that won the 1984, '87 and '91 Canada Cups, and also won six NHL Stanley Cups -- five with Edmonton and one with the Rangers.