Dekker is a surname. Notable people with the surname include:
Albert Dekker (1905–1968), American actor and politician
Desmond Dekker (1941–2006), Jamaican singer
Eduard Douwes Dekker (1820–1887), Dutch writer; also known as Multatuli
Ernest Douwes Dekker (1879–1950), Dutch politician and writer
Erik Dekker (born 1970), former Dutch professional cyclist
Femke Dekker (born 1979), Dutch rower
Fred Dekker (born 1959), American film director and writer
Inge Dekker (born 1985), Dutch competitive swimmer
Jeremias de Dekker (c. 1610 – 1666), Dutch poet
John Dekker, volleyball player
John Dekker (Wing Commander), computer game character
Laura Dekker (born 1995), Dutch solo sailor
Lia Dekker (born 1987), Dutch competitive swimmer
Mark Dekker (born 1969), Zimbabwean cricketer
Ron Dekker (born 1966), former Dutch competitive swimmer
Sander Dekker (born 1975), Dutch politician
Ted Dekker (born 1962), Indonesian-born American author
Theodorus Dekker (born 1927), mathematician
Thomas Dekker (born 1987), American actor
Thomas Dekker (born 1984), Dutch professional cyclist
Thomas Dekker (c. 1572 – 1632), English writer
Wisse Dekker (born 1924), Dutch businessman and former CEO of Philips
Dekker Dreyer (born 1980), American film director and producer