Breuil was educated at the Sorbonne and the Catholic Institute in Paris. Shortly after being ordained an abbé (1897), he developed a strong interest in Paleolithic (Paleolithic Period) art, and he devoted much of his life to studying examples of prehistoric art in southern France, northern Spain, and, during and after World War II, southern Africa.

Among his many important contributions to the field was a system of classification and chronology that he assigned to objects of art from the ice age. In particular, his paper "Les Subdivisions du Paléolithique supérieur et leur signification" (1912; “The Subdivisions of the Upper Paleolithic and Their Meaning”) established for the period a classification system that is of enduring value. In his attempt to explain the significance of these Ice Age objects, he developed a theory of “sympathetic magic,” assuming, for example, that certain images were made in order to promote fertility or a successful hunt. His views held sway in the field for much of the 20th century, but they have since been largely superseded.

Other important examples of his more than 600 publications, illustrated with his own copies of cave paintings and engravings, are La Caverne d'Altamira à Santillane près Santander (Espagne) (1906; The Cave of Altamira at Santillana del Mar, Spain), with Émile Cartailhac; La Caverne de Font-de-Gaume aux Eyzies (Dordogne) (1910; “The Cave of Font-de-Gaume near 【Les】 Eyzies (Dordogne)”), with Louis Capitan and Denis Peyrony; and Les Combarelles aux Eyzies (Dordogne) (1924; “Les Combarelles near 【Les】 Eyzies (Dordogne)”), also with Capitan and Peyrony. His Quatre cents siècles d'art pariétal (1952; Four Hundred Centuries of Cave Art) reveals his great scope of activities in this field. He taught at the Institute of Human Paleontology, Paris (from 1910), and at the Collège de France (1929–47).