Birt is a surname. Notable people with the surname include:
- Charlie Birt (born 1942), Canadian politician
- Fred Birt (1886–1956), Welsh rugby union player
- Jill Birt (fl. 1983–present), keyboardist in Australian band The Triffids
- John Birt (footballer) (born 1937)
- John Birt (politician) (1873–1925), Australian politician
- John Birt, Baron Birt (born 1944), Director-General of the British Broadcasting Corporation 1992–2000
- Michael Birt (barrister) (born 1948), lawyer and Bailiff of Jersey in the Channel Islands
- Michael Birt (biochemist) (1932–2001), Australian academician
- Peter Birt (c. 1723–1791), English businessman
- Suzanne Birt (born 1981), Canadian curler
- Travis Birt (born 1981), Australian former cricketer
- William Radcliffe Birt (1804–1881), British astronomer