Spencer Davis (born Spencer David Nelson Davis, 17 July 1939, Swansea, South Wales) is a musician and multi-instrumentalist, and the founder of the 1960s rock band, the Spencer Davis Group.

His father served as a paratrooper. Influenced by his Uncle Herman's mandolin playing, Spencer Davis began learning to play harmonica and accordion at the age of six. He then attended Dynevor Grammar School where he passed seven GCE O-level examinations. He moved to London when he was sixteen and began working in the Civil Service as a clerical officer at the Post Office Savings Bank in Hammersmith and for HM Customs and Excise. He then went back to his old school to study for A-levels in languages. In 1960 he moved to Birmingham, England to read German at the University of Birmingham. In music circles, Davis was later known as "Professor".

His early musical influences were skiffle, jazz, and blues, the mainstays of popular music in the early 1960s. Influential artists include Big Bill Broonzy, Huddy Ledbetter, Buddy Holly, Davey Graham, John Martyn, Alexis Korner and Long John Baldry. By sixteen, Davis was hooked on the guitar and the American rhythm and blues music making its way across the Atlantic. With few opportunities to hear R&B in England, Davis sought out any performance that came to town. When he heard a Dixieland band perform a skiffle version of the R&B song "John Henry", Davis formed a band called The Saints with Bill Perks, who later changed his name to Bill Wyman.