De Witt is a surname of Dutch origin meaning "the white". Notable people with the surname include:
De Witt (family), a patrician family from the Dutch Golden AgeJohan de Witt (1625–1672), Grand Pensionary of HollandCornelis de Witt (1623–1672), Dutch politicianAndries de Witt (1573–1637), Grand Pensionary of HollandJacob de Witt (1589–1674), burgomaster of DordrechtJacob De Witt (1785–1859), Canadian politicianAlexander De Witt (1798–1879), American politicianBryce De Witt (1923–2004), Theoretical physicistCécile DeWitt-Morette (1922-), Theoretical physicistDavid M. De Witt (1837–1912), American politicianFrancis B. De Witt (1849–1929), American politicianJacob H. De Witt (1784–1867), American politicianSimeon De Witt (1756–1834), American cartographer