| James Robert Martin Jr. | |
| Office: | Senior judge of the United States District Court for the District of South Carolina |
| Term Start: | November 30, 1979 |
| Term End: | November 14, 1984 |
| Office1: | Chief Judge of the United States District Court for the District of South Carolina |
| Term Start1: | 1965 |
| Term End1: | 1979 |
| Predecessor1: | Office established |
| Successor1: | Robert W. Hemphill |
| Office2: | Judge of the United States District Court for the District of South Carolina |
| Term Start2: | November 1, 1965 |
| Term End2: | November 30, 1979 |
| Appointer2: | operation of law |
| Predecessor2: | Seat established by 79 Stat. 591 |
| Successor2: | G. Ross Anderson |
| Office3: | Chief Judge of the United States District Court for the Western District of South Carolina |
| Term Start3: | 1962 |
| Term End3: | 1965 |
| Predecessor3: | Charles Cecil Wyche |
| Successor3: | Office abolished |
| Office4: | Judge of the United States District Court for the Eastern District of South Carolina Judge of the United States District Court for the Western District of South Carolina |
| Term Start4: | September 18, 1961 |
| Term End4: | November 1, 1965 |
| Appointer4: | John F. Kennedy |
| Predecessor4: | Seat established by 75 Stat. 80 |
| Successor4: | Seat abolished |
| Birth Name: | James Robert Martin Jr. |
| Birth Date: | 30 November 1909 |
| Birth Place: | Greenville, South Carolina |
| Education: | School of Law (LL.B.) |
James Robert Martin Jr. (November 30, 1909 – November 14, 1984) was a United States district judge of the United States District Court for the Eastern District of South Carolina, the United States District Court for the Western District of South Carolina and later the United States District Court for the District of South Carolina.
Born in Greenville, South Carolina, Martin received a Bachelor of Laws from Washington and Lee University School of Law in 1931. From 1931 to 1944 he was in private practice in Greenville. He was a member of the South Carolina House of Representatives from Greenville County from 1943 to 1944. He was a judge of the Thirteenth Judicial Circuit of South Carolina from 1944 to 1961.
Martin was nominated by President John F. Kennedy on August 30, 1961, to the United States District Court for the Eastern District of South Carolina and to the United States District Court for the Western District of South Carolina, to a new joint seat created by 75 Stat. 80. He was confirmed by the United States Senate on September 8, 1961, and received his commission on September 18, 1961. He served as Chief Judge of the Western District from 1962 to 1965. He was reassigned by operation of law to the United States District Court for the District of South Carolina on November 1, 1965, to a new seat authorized by 79 Stat. 951. He served as Chief Judge from 1965 to 1979. He assumed senior status on November 30, 1979. Martin served in that capacity until his death on November 14, 1984.