Physogaleus is a genus of prehistoric shark that lived from the Eocene to the Miocene, approximately 56–15.97 million years ago.
These sharks are known only from fossil teeth and isolated vertebrae. The teeth are similar to those of the modern tiger shark, but smaller. It was initially thought that the teeth belonged to an extinct species of tiger shark in the genus Galeocerdo, but later the numerous differences in their anatomy led researchers to classify sharks in the group Physogaleus. The teeth lack the characteristic lateral serrations of the tiger shark Galeocerdo; they are narrower and may have twisted crowns. These features suggest a possible diet of bony fishes, similar to that of modern sand tiger sharks.
