Dubnyk was drafted with the 14th overall pick by the Edmonton Oilers in the 2004 NHL Entry Draft. He made his NHL debut with the Oilers on November 28, 2009 in a 7–3 loss to the Vancouver Canucks. He recorded his first NHL win on March 21, 2010 in a 5–1 victory over the San Jose Sharks. He was re-signed to a two-year contract by the Oilers on July 13, 2010.