Named after the town hall of Montreuil, built in the 1930s.
Montreuil comes from the Latin Monasteriolum, 'little monastery'. A place of that name appears in an ordinance of the Merovingian king Theuderic IV dated 6 March 722, though the document may be an 11th-century forgery. The name Montreuil-sous-Bois, still sometimes used, was officially dropped for plain Montreuil by the town council on 12 July 1951.