Eugène Lefèvre-Pontalis (12 February 1862 – 31 October 1923) was a French medievalist and archeologist. Following his studies at the Lycée Condorcet, in 1881 he entered the École Nationale des Chartes, where he wrote a thesis on religious architecture in the former Diocese of Soissons in the 11th and 12th centuries. During his studies, he worked at the Mazarine Library and apprenticed with Alphonse Simil, an architect in the Commission des Monuments historiques. In 1894, he became assistant in medieval archaeology at the École Nationale des Chartes. In 1911 he became the professor.