| Thomas Long | |
| Office1: | Ontario MPP |
| Term Start1: | 1875 |
| Term End1: | 1883 |
| Predecessor1: | New riding |
| Successor1: | Orson James Phelps |
| Constituency1: | Simcoe West |
| Party: | Conservative |
| Birth Date: | 7 August 1836 |
| Birth Place: | Limerick, Ireland |
| Death Place: | Toronto, Ontario |
| Occupation: | Merchant |
Thomas Long (August 7, 1836 - October 9, 1920) was an Ontario merchant and political figure. He represented Simcoe West in the Legislative Assembly of Ontario as a Conservative from 1875 to 1883.
He was born in County Limerick, Ireland in 1836, began his education there and went to Simcoe County in Canada West in 1850, where he apprenticed with a merchant. He finished his schooling in Buffalo, New York. Long moved to Collingwood in 1857, where he managed a store for merchants before going into business for himself the following year. He married Ann Patton in 1861. In 1868, his brother joined him in the business, which include the sale of dry goods, clothing and groceries, a flour mill and steamboats. He served on the town council from 1864 to 1870. Long was a director of the Lake Superior Navigation Company and of the Georgian Bay Transportation Company. He died at Toronto in 1920.[1]