Kevin Bean, 36, portrays a character named "Blitzkrieg" with the World Wide Wrestling Alliance, WPVI reported.
Video surfaced of him at a show in Quakertown carrying a flag bearing the German Iron Cross and chanting a Nazi salute.
"This video makes me sick. Watching the guy do Nazi salutes on his way to the ring while children in the crowd cheer him on like a good guy is terrifying," tweeted Ryan Satin, the owner of ProWrestlingSheet.com.
Bean has been a teacher with the Spring-Ford Area School district since 2004, according to the district website. Superintendent David Goodin released a statement to WPVI that Bean is subject of an "ongoing internal investigation."
"I want to assure you that the actions portrayed in this video do not represent the core values of the school district," said Goodin. "As an educational organization, we pride ourselves in providing a safe and nurturing learning environment."
Attempts to reach Bean have been unsuccessful, according to the Mercury.
Bean is listed on WWWA's website as one of its "superstars," alongside performers named "King Blackie," "Slayer" and "Roadblock."
WWWA president Dino Sanna defended Bean in an interview with The Blast. He called Bean a "good guy and not a hateful person."
He also claimed during the interview many of the children in the stands were his students.