Dion Francis DiMucci (born July 18, 1939), better known mononymously as Dion, is an American singer and songwriter. His music incorporates elements of doo-wop, pop, rock, R&B, folk and blues. Initially the lead singer of the vocal group Dion and the Belmonts, Dion embarked on a solo career, and was one of the most prominent rock and roll performers of the pre-British Invasion era. He had 39 Top 40 hits in the late 1950s and early 1960s as a solo performer, or with the Belmonts and the Del-Satins. He is best remembered for his signature hit songs "Runaround Sue", "The Wanderer", "Ruby Baby" and "Lovers Who Wander", among others.

Dion continued making music after his popularity waned in the mid-1960s, and toward the end of the decade he shifted his style with more mature and contemplative songs, such as "Abraham, Martin and John".

During the 1980s, Dion produced several Christian albums, winning a GMA Dove Award in 1984 for the album I Put Away My Idols. He returned to secular music in the late 1980s with Yo Frankie (1989). Between the mid-2000s and 2024, Dion released seven chart-topping blues albums (three at No. 1). Critics who had dismissed his early work, labeling him as a teen idol, praised his later work and noted the influence he has had on other musicians.

A Grammy-nominated artist, Dion has released over 40 albums, and scored eleven Top 10 hits (including with the Belmonts) on the US Billboard Hot 100 chart. He was inducted into the Rock and Roll Hall of Fame in 1989. In 2002, Dion was inducted into the Grammy Hall of Fame for "Runaround Sue". Recent album awards include: Favorite Blues Album for New York Is My Home (2016), Favorite Compilations and Reissues for Kickin Child: Lost Columbia Album 1965 (2017) and Favorite Blues Album for Blues with Friends (2020).