| State House: | Mississippi |
| District: | Coahoma County |
| Termstart: | January 1916 |
| Termend: | January 1920 |
| Birth Date: | 12 February 1860 |
| Birth Place: | Smyrna, TN |
| Office1: | Mayor of Coahoma, Mississippi |
| Termstart1: | January 27, 1898 |
| Termend1: | 1914 |
| Party: | Democrat |
| Death Place: | Memphis, TN |
Robert Locke Ralston (1860-1926) was a Democratic member of the Mississippi House of Representatives, representing Coahoma County, from 1916 to 1920.
Robert Locke Ralston was born in Smyrna, Rutherford County, Tennessee, on February 12, 1860.[1] He was the son of Robert Lock Ralston and Mary M. (Stephens) Ralston. The junior Robert was a farmer and a planter. He married Mary Elizabeth Shaw in 1891. On January 27, 1898, he was appointed the mayor of Coahoma, Mississippi, a position in which he served for 16 years.[2] He was elected to the Mississippi House of Representatives as a Democrat to represent Coahoma County in November 1915, for the 1916–1920 term. Ralston died in Memphis, Tennessee, on April 3, 1926.[3]