"Little Willy" is a song written by songwriters Nicky Chinn and Mike Chapman and performed by the British glam rock band The Sweet, released in 1972 as a non-album single in the UK, peaking at #4 in the best seller charts. It was released in the US in September 1972 and also appeared on their US debut album The Sweet and became their biggest hit in the US, reaching #3 on the Billboard Hot 100. Billboard ranked it as the #18 song for 1973. "Little Willy" was used extensively in the pilot of the television series Life on Mars.