| Samuel James Ervin III | |
| Office: | Chief Judge of the United States Court of Appeals for the Fourth Circuit |
| Term Start: | 1989 |
| Term End: | 1996 |
| Predecessor: | Harrison Lee Winter |
| Successor: | J. Harvie Wilkinson III |
| Office1: | Judge of the United States Court of Appeals for the Fourth Circuit |
| Term Start1: | May 23, 1980 |
| Term End1: | September 18, 1999 |
| Appointer1: | Jimmy Carter |
| Predecessor1: | Seat established by 92 Stat. 1629 |
| Successor1: | Allyson K. Duncan |
| Birth Date: | 2 March 1926 |
| Birth Place: | Morganton, North Carolina |
| Death Place: | Morganton, North Carolina |
| Children: | Sam J. Ervin IV Robert C. Ervin |
| Father: | Sam Ervin |
| Education: | Davidson College (BS) Harvard Law School (LLB) |
Samuel James Ervin III (March 2, 1926 – September 18, 1999) was a United States circuit judge of the United States Court of Appeals for the Fourth Circuit and the son of United States Senator Sam Ervin.
Ervin was born in Morganton, North Carolina. He received a Bachelor of Science from Davidson College in 1948 and a Bachelor of Laws from Harvard Law School in 1951. He served in the United States Army from 1944 to 1946 and from 1951 to 1952. He was in private practice of law in Morganton from 1952 to 1967. He was the solicitor for the Burke County, North Carolina Board of Commissioners, from 1954 to 1956. He was a Member of the North Carolina House of Representatives from 1965 to 1967. He was a judge of the Superior Court of North Carolina from 1967 to 1980.
Ervin was nominated by President Jimmy Carter on April 2, 1980, to the United States Court of Appeals for the Fourth Circuit, to a new seat created by 92 Stat. 1629. He was confirmed by the United States Senate on May 21, 1980, and received his commission on May 23, 1980. Ervin served as Chief Judge of the court from 1989 to 1996. He served on the court until his death on September 18, 1999, in Morganton. Among others, he was survived by his sons, Sam J. Ervin IV and Robert C. Ervin, both of whom became judges.