| James Sumner | |
| Birth Name: | James Gaffield Sumner |
| Birth Date: | 16 August 1851 |
| Birth Place: | Boston, Massachusetts |
| Death Place: | Cambridge, Massachusetts |
| Nationality: | American |
| Known For: | Baseball umpire |
| Employer: | National League |
| Years Active: | 1876–1878 |
James Gaffield Sumner (August 16, 1851 – April 21, 1881), was an American professional umpire in Major League Baseball. He officiated 28 games as a National League umpire from 1876 until 1878.[1]