After finishing his education, Strobl became impressed enough by Snow White and the Seven Dwarfs to seek a job at Walt Disney Studios. After a refusal, he eventually was hired in 1938. He worked as an animator on Fantasia, Dumbo, and Pinocchio before he left the studio to fight in World War II.
In 1942, Strobl saved a seven-year-old girl from drowning while working for an Army propaganda unit. He returned to animation after the war, but moved over to the comics field, and after a few commercial artist jobs, he started working for Western Publishing in 1947.
At Western, he illustrated primarily Disney comics, especially from the Duck universe. Starting with a Bucky Bug story for Walt Disney's Comics and Stories #100 in 1949, Strobl had a long and impressive production of Disney comics. He did comic book stories for Western until 1968, and for the Disney Studio Program from 1963 to his retirement in 1987. Although during his career he primarily illustrated stories written by others, he wrote some of his stories himself. Strobl also illustrated some stories written by Carl Barks after the latter's 1966 retirement. The most significant of these is "King Scrooge the First" (Uncle Scrooge #71).
In the Hall of Fame series of hardcover books devoted to the greatest Duck (and Mouse) comics artists, published in Norwegian, Danish and Swedish by Egmont, Volume 15 (2006) is dedicated to Strobl's work.