Blue Cheer was a San Francisco based power trio of the late 1960s. The band burst into national consciousness with a cover of "Summertime Blues" (originally by Eddie Cochran) from their debut album Vincebus Eruptum (1968).

The band was named after a strain of LSD promoted by underground chemist and Grateful Dead backer Owsley Stanley; the drug was named for a popular detergent.

The group's sound was hard to categorize, but was definitely blues-based, psychedelic, and very loud. The band has been subsequently acclaimed as an influence on garage rock, punk music, heavy metal, and grunge.

The group underwent several personnel changes before the 1968 release of Outsideinside, and then through yet more changes before 1969's New! Improved! Blue Cheer, followed by Blue Cheer. 1970 saw the release of Human Being and then 1971's Oh! Pleasant Hope.