| Pre-Nominals: | Baron |
| Charles Lemonnier | |
| Post-Nominals: | GBE |
| Birth Name: | Charles Jean Maurice Lemonnier |
| Birth Date: | 1860 1, df=yes |
| Birth Place: | Mons, Belgium |
| Death Place: | Brussels, Belgium |
| Nationality: | Belgian |
| Baron | |
| Occupation: | politician |
Baron Charles Jean Maurice Lemonnier (12 January 1860 – 11 September 1930) was a Belgian liberal politician and mayor of the City of Brussels.
Charles Lemonnier was a lawyer, mining engineer and as a politician he was alderman ad-interim burgomaster of Brussels. He was also a member of parliament. During World War I he took over as burgomaster of Brussels, while Adolphe Max was held in captivity by the Germans.