Lydia Rabinowitsch-Kempner (August 22, 1871 - August 3, 1935) was an Russian-American physician. She was educated privately in Latin and Greek, and studied natural sciences at the universities of Zurich and Bern (MD). After graduation she went to Berlin, where Professor Robert Koch permitted her to pursue her bacteriological studies at the Institute for Infectious Diseases. She became the second woman in Prussia employed as a professor, and the first in Berlin. In 1895 she went to Philadelphia, where she was appointed lecturer and, professor at the Woman's Medical College of Pennsylvania and founded a bacteriological institute. In 1896 she delivered a lecture on the study of medicine by women at the International Congress of Women. She died in 1935 in Berlin, aged 63, from undisclosed causes.