Sayer is a surname, and may refer to:
- Amy Sayer (born 2001), Australian footballer
- Andrew Sayer (born 1949), British social scientist and philosopher of science
- George Sayer (biographer) (1914–2005), English teacher and biographer
- George Sayer (MP) (1655–1718), English politician, MP for Canterbury
- Gerry Sayer (1905–1942), British pilot and air force officer
- Guillaume Sayer (c.1801–c.1849), Métis fur trader
- Ian Sayer (born 1945), English writer and businessman
- Jess Sayer, New Zealand actress and playwright
- John William Sayer (1879–1918), English non-commissioned officer in World War I and Victoria Cross recipient
- Leo Sayer (born 1948), British singer-songwriter
- Malcolm Sayer (1916–1970), British aircraft and car designer
- Paul Sayer (born 1955), English novelist
- Peter Sayer (born 1955), Welsh professional footballer
- Phil Sayer (1953–2016), British voice artist
- Richard Sayer, English politician, MP for Grampound, 1588–1589
- Roger Sayer, British organist
- Sylvia Sayer (1904–2000), English conservator
- William Sayer (1857–1943), Australian lawyer and politician