Douglas Lee Dorman (September 15, 1942 – December 21, 2012) was an American bass guitarist best known as a member of the psychedelic rock band Iron Butterfly.

They are best known for the 1968 hit "In-A-Gadda-Da-Vida", providing a dramatic sound that led the way towards the development of hard rock and heavy metal music.

The song, originally written by Doug Ingle as "In the Garden of Eden" but as a result of singing the first draft whilst intoxicated was misheard by drummer Ron Bushy as "In-A-Gadda-Da-Vida", went to number thirty on the Billboard Hot 100, and charted highest in the Netherlands, where it went to number seven.

Their music has found a significant impact on the international rock scenes, influencing numerous acts such as Black Sabbath, AC/DC, Rush, Alice Cooper, Mountain, Uriah Heep, Soundgarden, Stone Temple Pilots, Slayer, King Gizzard & the Lizard Wizard, and Queens of the Stone Age.

The band was plagued from its inception with significant problems, including lawsuits involving Evans, Reinhardt and Dorman with their former bands, and a dispute over musical style with their record label, Capricorn Records Dorman was raised in St. Louis, Missouri, and moved to San Diego in the 1960s.