Carl Ludwig Max Wittmack (26 September 1839 in Hamburg – 2 February 1929 in Berlin) was a German botanist.

He received his doctorate degree in 1867 with a dissertation on the banana, Musa Ensete, from the University of Göttingen.

In the same year, he worked as curator at the Agricultural Museum in Berlin, where he managed plant breeding.

He was professor of Botany at the Agricultural College in Berlin (1880-1913), professor of botany at the University of Veterinary Medicine in Berlin (1880-1920), director of the Experiment Station of the Association of German Müller (1875-1905), a member of the department for seed cultivation in the German Agricultural Society (1883-1924), and Director of the Agricultural Institute (1889-91 and 1910-13).

From 1887, he was editor of the magazine Gartenflora, founded in 1852 by the German botanist Eduard August von Regel.