Robert Allan Edgar (born 1940) is a United States federal judge.
Born in Munising, Michigan, Edgar received a B.A. from Davidson College in 1962 and a law degree from Duke University School of Law in 1965. He was in the United States Army from 1965 to 1967. He was in private practice in Chattanooga, Tennessee from 1967 to 1985. He was a representative in the Tennessee State Legislature from 1970 to 1972.
On February 26, 1985, Edgar was nominated by President Ronald Reagan to a seat on the United States District Court for the Eastern District of Tennessee vacated by H. Ted Milburn. Edgar was confirmed by the United States Senate on April 15, 1985, and received his commission on April 16, 1985. He served as chief judge from 1998 to 2005, assuming senior status on October 7, 2005.