| Charles Ralph Simpson III | |
| Office: | Senior Judge of the United States District Court for the Western District of Kentucky |
| Term Start: | February 1, 2013 |
| Office1: | Chief Judge of the United States District Court for the Western District of Kentucky |
| Term Start1: | 1994 |
| Term End1: | 2001 |
| Predecessor1: | Ronald Edward Meredith |
| Successor1: | John G. Heyburn II |
| Office2: | Judge of the United States District Court for the Western District of Kentucky |
| Term Start2: | August 4, 1986 |
| Term End2: | February 1, 2013 |
| Appointer2: | Ronald Reagan |
| Predecessor2: | Charles M. Allen |
| Successor2: | David J. Hale |
| Birth Name: | Charles Ralph Simpson III |
| Birth Date: | 8 July 1945 |
| Birth Place: | Cleveland, Ohio, U.S. |
| Education: | University of Louisville (BA, JD) |
Charles Ralph Simpson III (born July 8, 1945) is a senior United States district judge of the United States District Court for the Western District of Kentucky.
Born in Cleveland, Ohio, Simpson received a Bachelor of Arts degree from the University of Louisville in 1967 and a Juris Doctor from the University of Louisville School of Law in 1970. He was in private practice in Louisville, Kentucky from 1971 to 1986. He was a part-time staff counsel, Jefferson County Judge/Executive from 1978 to 1984, and also a Jefferson County alcoholic beverage control administrator from 1983 to 1984. He was the city clerk of the City of Rolling Fields from 1985 to 1986.
On June 6, 1986, Simpson was nominated by President Ronald Reagan to a seat on the United States District Court for the Western District of Kentucky vacated by Judge Charles M. Allen. Simpson was confirmed by the United States Senate on August 1, 1986, and received his commission on August 4, 1986. He served as chief judge from 1994 to 2001. He assumed senior status on February 1, 2013.