Maurits Willem van der Valk was a Dutch landscape and vedute painter and art critic.

Van der Valk studied from 1878 to 1884 at the Rijksakademie van beeldende kunsten in Amsterdam with August Allebé .

Together with his fellow students, he founded the Kunstenaarsvereniging Sint Lucas in 1881. He painted, drew, etched and lithographed still lifes with shells and landscapes.

He changed his place of residence and work several times: he stayed in Amsterdam until 1890, then came to France (first Paris, later Auvers-sur-Oise), then back to Amsterdam from 1893 to 1902, Scherpenzeel after 1903, Amersfoort from 1905 to 1909, Leiden from 1909 to 1919, Vreeland to 1920, Laren (North Holland) 1920 and settled in Amsterdam in 1925. In 1885 he became a member of " Arti et Amicitiae ".

From 1885 he wrote art reviews for “De Nieuwe Gids”, the magazine of the Tachtigers artist group, under the pseudonym “J. Stemming ”or“ IN Stemming ”. From 1883 to 1890 he taught at a drawing school in Amsterdam. In 1889 his studio caught fire. With the insurance money he went to Paris, where he lived for a while and where he met his future wife, Baukje van Mesdag. In 1893 the family returned to the Netherlands. After his return he taught privately to Johann Georg van Caspel and Reinier de Vries (1874–1953), among others.