Many of the comedy films Van Dyke starred in throughout the 1960s were relatively unsuccessful at the box office, including What a Way to Go! with Shirley MacLaine, Lt. Robin Crusoe, U.S.N., Fitzwilly, The Art of Love with James Garner and Elke Sommer, Some Kind of a Nut, Never a Dull Moment with Edward G. Robinson, and Divorce American Style with Debbie Reynolds and Jean Simmons. But he also starred as Caractacus Pott (with his native accent, at his own insistence, despite the English setting) in the successful musical version of Ian Fleming's Chitty Chitty Bang Bang (1968), which co-starred Sally Ann Howes and featured the same songwriters (The Sherman Brothers) and choreographers (Marc Breaux and Dee Dee Wood) as Mary Poppins.
In November 1959, Van Dyke made his Broadway debut in The Girls Against the Boys. He then played the lead role of Albert Peterson in Bye Bye Birdie, which ran from April 14, 1960, to October 7, 1961. In a May 2011 interview with Rachael Ray, Van Dyke said that when he auditioned for a smaller part in the show he had no experience as a dancer, and that after he sang his audition song he did an impromptu soft-shoe out of sheer nervousness. Gower Champion, the show's director and choreographer, was watching, and promptly went up on stage to inform Van Dyke he had the lead. An astonished Van Dyke protested that he could not dance, to which Champion replied: "We'll teach you". That musical won four Tony awards including Van Dyke's Best Featured Actor Tony, in 1961. In 1980, Van Dyke appeared as the title role in the first Broadway revival of The Music Man.