Prince of Darkness is a box set of four CDs by Ozzy Osbourne released in 2005. The first two CDs are Osbourne's solo work containing various studio recordings, live tracks, b-sides, demos and outtakes, and the last two CDs are collaborations on disc three and cover songs on disc four. The cover versions were recorded for this box set compilation, but were released on a stand-alone album entitled Under Cover later in the year.

John Michael "Ozzy" Osbourne is an English musician and media personality. He rose to prominence during the 1970s as the lead singer of the heavy metal band Black Sabbath, during which period he adopted the nickname "Prince of Darkness".