Peter Behn (born October 24, 1934) is an American former voice actor and child actor. He is best known for providing the voice of the young Thumper in the film Bambi.

Behn's only film role to date is voicing the young Thumper in the 1942 Disney film Bambi, a role he was actually uncredited for. Though a small role, the character Thumper and the movie Bambi are cultural icons, giving Behn immortality among Disney fans of all generations. Behn appeared in a documentary about the making of Bambi in 1994. He was 4 years old when he voiced the role.