Matti Kalle Onnismaa (born October 21, 1959) is a Finnish actor. He made his leading performance debut in black comedy film Euthanizer (2017). He has also appeared in films such as The Winter War (1989), The Romanov Stones (1993), Drifting Clouds (1996), Pearls and Pigs (2003), Matti: Hell is for Heroes (2006), Lights in the Dusk (2006), V2: Dead Angel (2007), The Home of Dark Butterflies (2008), Hellsinki (2009), The Other Side of Hope (2017), Rendel (2017) and The Woodcutter Story (2022).