The 2003 Canadian Open curling men's Grand Slam tournament was held November 6–9, 2003 at the Keystone Centre in Brandon, Manitoba. The total purse for the event was $100,000. The tournament format was a triple knock out with an 8 team playoff. The playoffs were televised on Rogers Sportsnet. Glen Despins of Regina, Saskatchewan won his lone career grand slam event, earning $30,000 for his team.