Gustav is a caterpillar character from Sesamstrasse, the German co-production of Sesame Street.

Gustav is Rumpel's pet caterpillar who lives in his barrel. He is the only character Rumpel shows his soft-natured side to. Gustav doesn't speak.

Gustav was added to the Sesamstrasse cast in 2002. He was based on Oscar's pet worm Slimey.