| Birth Date: | 7 July 1835 |
| Birth Place: | Paris |
| Citizenship: | French |
| Fields: | Zoology |
| Workplaces: | National Museum of Natural History (France) |
| Children: | French zoologist Pierre Marie Henri Fischer (1865-1916) |
Paul Henri Fischer (also spelled Paul-Henri Fischer), (7 July 1835 Paris - 29 November 1893) was a French physician, zoologist and paleontologist. He is generally known as Paul Fischer.
He studied science and medicine, securing doctorates in both, and became assistant in paleontology at the National Museum of Natural History in Paris. He was made assistant naturalist there in 1872. Beginning in 1856, he was joint editor, with A. C. Bernardi to start with, of the Journal de Conchyliologie. He served several terms as president of the Société Géologique de France and the Société Zoologique de France. In 1880, he was a member of the commission for submarine dredging.