David Oswald Nelson (October 24, 1936 – January 11, 2011) was an American actor. He was the elder son of entertainment couple Harriet Hilliard Nelson and Ozzie Nelson and the older brother of musician Ricky Nelson.

Nelson's acting career started in 1949 when he and his brother began playing themselves on his parents' radio series The Adventures of Ozzie and Harriet, which lasted until 1954. His film debut came in Here Come the Nelsons, released in 1952.

Also in 1952 Nelson continued playing himself on the television version of The Adventures of Ozzie and Harriet, which ran until 1966.Starting in the early 1960s, he directed about a dozen episodes of the show.

From the 1970s through 1990 Nelson had roles in Smash-Up on Interstate 5, Up In Smoke, The Love Boat, High School U.S.A., and A Family for Joe. Nelson's last film appearance was in John Waters' 1990 film Cry-Baby.

Nelson died on January 11, 2011, in Century City, California, of complications of colon cancer.