Karl Frederick Grittner (November 22, 1922 – March 3, 2011) was an American educator and politician.
He lived with his wife and family in Saint Paul, Minnesota.
Grittner graduated from Hamline University in 1945 and went to the National Institute of Public Affairs in Washington, D.C. Grittner also received his master's and doctorate degrees from University of Minnesota.
He taught at Cleveland Junior High School in Saint Paul, Minnesota.
Grittner died from pancreatic cancer at his daughter's house in San Antonio, Texas.