Spiegle began his professional comics career in 1949 drawing the Hopalong Cassidy comic strip for Mirror Enterprises Syndicate. The strip was sold to King Features in 1951, and he continued to draw it until the strip was canceled in 1955. He was known for his comic adaptations of TV-series for Dell’s Four Color, which include Maverick, The Rifleman, Lawman and The Untouchables. He co-created Doctor Spektor with writer Donald Glut in 1972. He worked on Gold Key’s Staturday-morning TV animation title Hanna-Barbera Scooby-Doo... Where Are You! Spiegle later worked for DC Comics and worked on Blackhawk with Mark Evanier.
An artbook about his work, Dan Spiegle: A Life in Comic Art, authored by John Coates, was released in 2013 by TwoMorrows Publishing.
He is survived by his wife, Marie and four children.