Malarchuk, who was born in Grande Prairie, Alberta and raised in Edmonton, played junior hockey in the Western Hockey League. He went on to play professionally in the NHL for the Quebec Nordiques, the Washington Capitals, and the Buffalo Sabres, and in the IHL for the Las Vegas Thunder. In 1987, Malarchuk was named to the NHL All-Star team and, in 1989, was the recipient of the Punch Imlach award for leadership and dedication to the game of hockey.

After retiring from the NHL as a player, Malarchuk served as head coach of the IHL Las Vegas Thunder and the Idaho Steelheads. He was then a goaltending coach for the NHL Florida Panthers, Columbus Blue Jackets, Atlanta Thrashers, and Calgary Flames. Malarchuk was inducted into the New York State Hockey Hall of Fame in May 2022.

In 2008, Malarchuk survived a suicide attempt. After recovering physically, mentally, and emotionally, he became a mental health advocate and a renowned professional speaker on mental health. He speaks to his journey living with OCD, PTSD, depression, and anxiety. In recognition of his advocacy work, Malarchuk received an honourary doctorate from Nipissing University in 2017. In addition, Malarchuk is the author of The Crazy Game: How I Survived in the Crease and Beyond.