Mike Kostka (born November 28, 1985) is a professional ice hockey defenceman currently playing with the Toronto Maple Leafs of the National Hockey League.
After playing four seasons at the University of Massachusetts Amherst, he was signed to a professional contract by the Buffalo Sabres of the National Hockey League on March 25, 2008. He was assigned to the organization's American Hockey League affiliate (at the time), the Rochester Americans. In his second professional season he moved with the Sabres to new affiliate, the Portland Pirates before returning after two years to sign with the Rochester Americans for the 2010–11 season on August 24, 2010.
On June 30, 2011, Kostka was signed to a one-year NHL contract with then Rochester affiliate, the Florida Panthers.
On December 2, 2011, Kostka was traded by the Panthers, along with Evan Oberg, to the Tampa Bay Lightning for James Wright and Mike Vernace.
After helping Norfolk capture the Calder Cup, on July 1, 2012, Kostka was signed as a free agent to a one-year contract by the Toronto Maple Leafs.