Broca, who was born in Sainte-Fou-la-Grande, France, studied at the University of Paris and received his MD in 1849. In 1853 he was appointed assistant professor in the faculty of medicine. His specialty was the brain and, through surgical work and postmortem examination, he was able to demonstrate that damage to one particular region (the left inferior frontal gyrus, now also known as Broca's convolution) of the cortex was associated with impairment or loss of speech. This was one of the first conclusive demonstrations that control of different bodily functions resides in localized regions of the cerebral cortex.

Broca applied his knowledge of the brain to anthropology. He devised techniques of accurately measuring skulls to enable comparison between the different races of modern man and skulls unearthed at prehistoric sites. Broca's findings supported the then highly contentious theory of Charles Darwin that man, like other living things, had evolved from primitive ancestors. Broca helped found several notable anthropological institutions, including the Société d'Anthropologie de Paris (1859) and the Ecole d'Anthropologie (1876), thus helping to establish anthropology as a respectable branch of science.