Stanisław Lentz (April 23, 1861 – October 19, 1920) was a Polish painter, portraitist, illustrator, and a professor at the Academy of Fine Arts in Warsaw from 1909.

In 1880–1884 he studied abroad at the Academy of Fine Arts in Munich with Alexander von Wagner and Gyula Benczúr, and in 1884–1887 at the Académie Julian in Paris.

At the Exposition Universelle in 1900 he won the award for the aesthetic qualities of Portret Mieczysława Frenkla (Portrait of Mieczysław Frenkel).

He was valued for his portraits created in the period 1900–1915, highlighting the blunt characteristics of the model, a synthetic form of the dark monochromatic colours and broad brushstrokes.

In the last period of his creativity he also undertook artworks memorializing the effort of the soldiers of the Polish Legions in World War I fighting for the country's independence.