Robby Robinson is originally from Litchfield, Illinois. He studied piano from age 7, saxophone from age 8, and started playing in rock bands at age 14. He majored in music at Southern Illinois University of Edwardsville. From high school through college, Robinson played in a variety of bands in the Southern Illinois-St. Louis area, after college he toured the US with Phil Driscoll and "Patch & Didi" (with his brother Rex Robinson, Lynn Hamman, and Didi Carr). The Robinson brothers moved to Los Angeles in 1976.

From 1976 to 1978 Robinson played, arranged, and produced with a broad range of musicians such as Liza Minnelli,Tom Jones, Alphonse Mouzon, Buddy Greco, and Les DeMerle. In 1978, at the recommendation of long-time friend Richie Gajate Garcia, Robinson joined Frankie Valli and The Four Seasons, he has been the group's music director, conductor and keyboardist for over 45 years.