Posthuma is a Dutch surname that may refer to: Carst Posthuma (1868–1939), Dutch cricket player Danielle Posthuma (born 1972), Dutch neuroscientist Douwe Bob Posthuma (born 1992), Dutch singer-songwriter, known simply as Douwe Bob Folkert Posthuma (1874–1943), Dutch politician Jan Posthuma (born 1963), Dutch volleyball player Joost Posthuma (born 1981), Dutch road bicycle racer