| James Barnes | |
| Office: | Member of the Legislative Assembly of New Brunswick |
| Alongside: | Urbain Johnson, Richard A. Poirier, Pierre H. Léger, Jean-Baptiste Goguen |
| Term Start: | 1896 |
| Term End: | 1908 |
| Constituency: | Kent |
| Birth Date: | 6 September 1842 |
| Birth Place: | Cornwall, Ontario |
| Spouse: | Julia Eliza Smith |
| Party: | New Brunswick Liberal Association |
| Occupation: | Farmer, contractor |
| Residence: | Buctouche, New Brunswick |
James Barnes (September 6, 1842 - November 8, 1924) was a farmer, lumberman, railway contractor and political figure in New Brunswick, Canada. He represented Kent County in the Legislative Assembly of New Brunswick from 1895 to 1908 as a Liberal member.
He was born in Cornwall and later came to Bouctouche, New Brunswick. Barnes married a Julia Eliza Smith there. He ran unsuccessfully for a seat in the provincial assembly in 1892.