Bob Sweeney was a graduate of Balboa High School (San Francisco) and San Francisco State College. He began his career on radio as an announcer and then comedian. From 1944 through 1948 he teamed with comedy partner Hal March in the successful "Sweeney and March Show" for CBS Radio. He went on to appear as a supporting character in various sitcoms in the early days of television including the role of Gilmore Cobb in the television version of "My Favorite Husband" (1953–54) with co-stars Joan Caulfield and Barry Nelson. Sweeney made appearances on "The Rifleman" also in "Our Miss Brooks" during its last two seasons of production (1955–1956) working alongside Eve Arden, Gale Gordon and Richard Crenna.
From 1956-1957 Sweeney starred in the TV sitcom The Brothers with co-star Gale Gordon (later of The Lucy Show). In 1959, he landed the lead role on the short-lived NBC television series Fibber McGee and Molly opposite Cathy Lewis. Unlike the wildly popularradio version of the show that featured Jim Jordan and Marian Jordan in the title roles, Fibber McGee failed on television and was cancelled after less than one season. That same year, Sweeney directed the 18-week NBC sitcom Love and Marriage set in Tin Pan Alley of New York City. His co-stars were William Demarest, Stubby Kaye, Jeanne Bal, and Murray Hamilton.
His most notable film credits as an actor include the role of the undertaker in John Ford's, The Last Hurrah (1958), as bad guy Harry Tupper in the Disney children's movie,Toby Tyler (1960) and as Mr. Harker in another Disney film Son of Flubber (1963). Bob Sweeney also appeared as Cousin Bob in Alfred Hitchcock's, Marnie (1964).
Sweeney is best known for his successes as a television director and producer, most notably as the director of the first three seasons of The Andy Griffith Show and as producer and/or director of episodes of several other highly successful TV series including Hawaii Five-O, That Girl, The Love Boat, Matlock and Dynasty. He also directed Gene Evans's unsuccessful 1976 CBS adventure series, Spencer's Pilots. Although Bob Sweeney never won an Emmy Award he was nominated on three occasions, twice for Hawaii Five-O(1971 and 1973) and once for The Love Boat (1983).
He and his wife Bev had one child, a daughter, Bridget.