Dion Phaneuf (born April 10, 1985) is a Canadian professional ice hockey defenceman currently playing for the Calgary Flames of the National Hockey League. Phaneuf was drafted ninth overall in the 2003 NHL Entry Draft by the Flames, and completed his junior hockey career in the in the spring of 2005 with the Western Hockey League's Red Deer Rebels.

Phaneuf was named to the "CHL First All-Star Team" for the 2003–04 and 2004–05 seasons. In 2004, he was awarded the Bill Hunter Memorial Trophy as the WHL's top defenceman, and was also named to the "WHL East First All-Star Team". In February, 2005, The Hockey News named him the number two hockey prospect in the world behind Russian Alexander Ovechkin. "Hockey's Future" listed Phaneuf as their #3 prospect behind forwards Ovechkin and Sidney Crosby, and predicted that he would win the James Norris Memorial Trophy multiple times in his NHL career.

Phaneuf made his NHL debut with the Flames on the opening night of the 2005–06 NHL season on October 5, 2005, in a 6–3 loss to Minnesota. He recorded his first point, first assist, and first goal on October 10, 2005, in a game against the Colorado Avalanche.