David Warren "Dave" Ellefson (born on 12 November 1964 in Jackson, Minnesota, United States) is an American bassist. He was a member of the band Megadeth. Along with Dave Mustaine, he is one of the founding members of the band. He currently lives in Scottsdale, Arizona.
He has also played with Soulfly, Avian, Temple of Brutality, F5, Killing Machine, Ministry, Hail! and Altitudes & Attitudes.