Daniel "Oz" Osbourne is a fictional character created by Joss Whedon for the television series Buffy the Vampire Slayer. The character is portrayed by Seth Green. Green also portrays the character in one episode of the spin-off series Angel.

Buffy the Vampire Slayer is an American supernatural drama television series created by writer and director Joss Whedon. The concept is based on the 1992 film, also written by Whedon, although they are separate and unrelated productions. Whedon served as executive producer and showrunner of the series under his production tag Mutant Enemy Productions. It premiered on March 10, 1997, on The WB and concluded on May 20, 2003, on UPN.