August Lemmer (1862 – date of death unknown) was a German artist.
After studying at the art academy of Karlsruhe from 1888–92 he remained in the capital of the Grand Duchy of Baden.
Lemmer made his name as a painter of impressionistic landscape, seascape, and city views.
He often painted images of Carniola, Trieste, Venice, and German cities such as Munich.
Lemmer also often painted images of fishing boats off the coast of Venice.