| Honorific-Prefix: | Mayor |
| Jacques Grenier | |
| Order: | 20th Mayor of Montreal |
| Term Start: | 1889 |
| Term End: | 1891 |
| Constituency: | Saint-Jacques |
| Predecessor: | John Abbott |
| Successor: | James McShane |
| Birth Date: | 20 January 1823 |
| Birth Place: | Berthier-en-Haut, Lower Canada |
| Death Place: | Montreal, Quebec, Canada |
| Profession: | businessman |
Jacques Grenier (20 January 1823 - 5 March 1909) was a Canadian businessman and politician. He was mayor of Montreal.
He was born in Berthierville.
He was the Liberal candidate to the provincial legislature in the district of Montréal-Est in 1878, but lost against Louis-Olivier Taillon.
Grenier was a City Councillor in Montreal from 1857 to 1860, from 1861 to 1865, from 1872 to 1873 and from 1874 to 1889. He resigned in 1889 to run for Mayor.
He was elected Mayor of Montreal in 1889, was re-elected in 1890, but was defeated in 1891.
After his death in 1909, he was entombed at the Notre Dame des Neiges Cemetery in Montreal.[1]