William Henry “Buddy” Deppenschmidt (February 16, 1936 – March 20, 2021) was an American jazz drummer.

Deppenschmidt’s father, a saxophone player, led an orchestra under the name Buddy Williams after playing with and arranging for Paul Whiteman, Jimmy and Tommy Dorsey, and Glenn Miller. When he was four, Deppenschmidt and his mother moved from Philadelphia to Richmond, Virginia.

Self-taught, he started playing drums professionally while in his teens and then went on the road with Ronnie Bartley’s Orchestra, a territory band which travelled in the western U.S. Returning to Richmond, he played with local bands and became the drummer for the Newton Thomas Trio (1954–59) which was also the rhythm section for the Billy Butterfield Quintet. The trio toured with Butterfield throughout the northeast and midwest (1958–59). When the Newton Thomas Trio played the Virginia Beach Jazz Festival, it received rave reviews on a bill that included the Dave Brubeck Quartet and the Charlie Byrd Trio. Two nights later, Charlie Byrd came into the Jolly Roger, the jazz club where Deppenschmidt was playing, and offered him the job as drummer with his trio. He played with the trio at the Showboat Lounge in Washington, D.C. from 1959–62.

Starting in February 1961, the Charlie Byrd Trio (Charlie Byrd, guitar, Keter Betts, bass, and Buddy Deppenschmidt, drums) visited South America, Central America, and Mexico on a goodwill tour sponsored by the U.S. State Department. This three-month cultural exchange included eighteen countries. While in Brazil, Deppenschmidt spent his free time with local musicians, teaching them American jazz and learning bossa nova from them. It was his idea to record an album combining jazz and bossa nova with Stan Getz.