In May 2005, Couture was drafted by the Ontario Hockey League (OHL)'s Ottawa 67's 12th overall in the 2005 OHL Priority Draft. He went on to score at a near point-per-game pace as a rookie with 64 points in 65 games in 2005–06, third in league rookie scoring behind John Tavares and Sergei Kostitsyn. The next season, in 2006–07, Couture was added to the OHL roster for the 2006 ADT Canada-Russia Challenge, replacing Jordan Staal, who was retained by the NHL's Pittsburgh Penguins. Couture was also selected to play for the Eastern Conference in the 2007 OHL All-Star Game, winning the shooting accuracy competition. After completing his second OHL season, where he improved to 78 points in 54 games, Couture was drafted ninth overall by the San Jose Sharks in the 2007 NHL Entry Draft.