Donker is a Dutch surname. Donker means "dark, somber" in modern Dutch, and was probably a character reference. Alternative spellings include Donkers, (de) Doncker and Donckers. People with these surnames include:

Donker Ad Donker (1933–2002), Dutch-born South-African publisher (born 1965), Dutch journalist (born 1940), Dutch illustrator Greetje Donker (1906–1993), Dutch dancer and choreographer Leendert Antonie Donker (1899–1956), Dutch politician Pieter Donker (1635–1668), Dutch painter Donker Curtius Dirk Donker Curtius (1792–1864), Dutch politician and Minister of Justice Janus Henricus Donker Curtius (1813–1879), Dutch diplomat and last director at Dejima (1778–1858), Dutch politician Doncker Herman Doncker (1600–1666), Dutch painter (1874–1917), Dutch illustrator and shadow puppeteer Tomás Doncker, American blues guitarist and singer De Doncker Eric De Doncker (born 1962), Belgian racing driver (born 1958), Belgian youth author Donckers Karin Donckers (born 1962), Belgian equestrian