Thomas George Kostopoulos (Greek: Θωμάς Κωστόπουλος; born January 24, 1979) is a Canadian former professional ice hockey player.

Kostopoulos was selected by the Pittsburgh Penguins in the seventh round (204th overall) of the 1999 NHL Entry Draft, and the 2017–18 season was his 19th year as a professional hockey player.

[5] Kostopoulos responded about the incident by saying," First and foremost, I sincerely regret the injuries suffered by Mike Van Ryn...this is an unfortunate turn of events.

"[6] NHL disciplinarian Colin Campbell said in announcing the suspension that while Van Ryn was not in a defenceless position, his injuries—including a concussion—were significant enough to warrant suspending Kostopoulos.

Kostopoulos was assessed a minor roughing penalty during the game, but then served a six-game suspension for making primary contact with the head.

[9] On March 5, 2013, the Pittsburgh Penguins signed Kostopoulos to a one-year two-way contract[10] but was claimed off waivers by the New Jersey Devils the following day.

[11] On September 3, 2013, Kostopoulos signed a one-year AHL contract to continue to play with and lead the Wilkes-Barre/Scranton Penguins.

[19] Kostopoulos is involved with the Canadian Cancer Society as well as Garth Brooks' Teammates For Kids Foundation.