The devastating news was shared on Stan's official Facebook page.
"We tragically lost our beloved Stan Kirsch on January 11," a statement read.
"He was so loved and we are all just devastated."
His wife Kristyn shared the statement on her own Facebook page as she thanked everyone for the "outpouring of love and support".
"I haven't been able to respond to all the texts, calls, emails - but have read or listened to every single one of them," she said.
"I feel surrounded by love and am forever grateful to each and every one of you."
Stan was best known for playing Richie Ryan in the Highlander TV series for six seasons from 1992-1998.
He also starred in a Friends episode as Ethan - one of Monica's dates who she later discovers is a high school student lying about his age.
The official Highlander Facebook page paid tribute to Stan in a post which praised his sense of humour, kindness and enthusiasm.
It read: “It is with great sadness that we acknowledge the passing of Stan Kirsch.
“Without Stan Kirsch, Highlander: The Series would have been far less. He brought a sense of humour, kindness and youthful enthusiasm to the character of Richie Ryan for six seasons.”
"He was nothing but kind, thoughtful and sincere. He was a warm presence that will be missed."