Wilhelm Trübner (February 3, 1851 – December 21, 1917) was a German realist painter of the circle of Wilhelm Leibl.

He published writings on art theory in 1892 and 1898, which express above all the idea that "beauty must lie in the painting itself, not in the subject". By urging the viewer to discover beauty in a painting's formal values, its colors, proportions, and surface, Trübner advanced a philosophy of "art for art's sake". In 1901 he joined the recently formed Berlin Secession, at the time Germany's most important forum for the exhibition of avant-garde art. From 1903 until his death in 1917 he was a professor at the Academy of Arts in Karlsruhe, also serving as director from 1904 to 1910.