Born in Zapponeta, Apulia, Di Bari was the youngest of ten children in a family of farmers. He gave up his accountancy studies to go to work in the North Italy, and after a brief stop in Rome he moved in Milan where he made many different jobs. In 1962, in Cologno Monzese, he won a song contest with a song of which he was also the author, "Piano pianino". In 1964 he got his first commercial success with the song "Amore ritorna a casa". Between 1965 and 1967 he entered the competition at three editions of the Sanremo Music Festival, in couple with Gene Pitney.
In 1970 Di Bari obtained a great commercial and critical success with the song "La prima cosa bella", which ranked second at the Sanremo Music Festival and first on the Italian hit parade. In 1971 he won the Sanremo Music Festival and Canzonissima, with the songs "Il cuore è uno zingaro" and "Chitarra suona più piano". In 1972, he won again the Sanremo Festival and represented Italy at the Eurovision Song Contest with the song "I giorni dell'arcobaleno" ("The Days of the Rainbow"). In the following years Di Bari grew his international popularity, especially in Latin America, where he recorded several albums in Spanish and where he gradually focused his career.