Walter Hopps died on March 20, 2005 at the Cedars-Sinai Medical Center in Los Angeles.
Hopps was one of the original owners of the Ferus Gallery which was the first gallery to show Warhol's Soup Cans in 1962 and during the same year he organized what is generally regarded as the first Pop exhibition in a museum, New Painting of Common Objects, at the Pasadena Art Museum (now the Norton Simon Museum). The following year he organized the first U.S. retrospective of Marcel Duchamp at the same museum.