Campbell's representative Bobbie Gale made the announcement Wednesday. The disease is in its early stages.
The 75-year-old's wife Kim also talked to People magazine and said they wanted to go public with his illness because they wanted fans to know if he has trouble onstage.
Campbell's CD "Ghost on the Canvas" is scheduled for release Aug. 30. He also is to go on "The Glen Campbell Goodbye Tour."
The Country Music Hall of Famer had pop and country hits with "Gentle on My Mind," "By the Time I Get to Phoenix," and perhaps his most famous song, "Rhinestone Cowboy." He also had his own TV show on CBS.
