Label: Sun (9) – SLP 1240, Sun (9) – LP-1240
Format: LP
Country: US
Released: 2016
Genre: Folk, Country
Style: Country, Rockabilly

Greatest! is a compilation album by American singer-songwriter Johnny Cash. It was released on October 19, 1959, by Sun Records after Cash had left the label and signed with Columbia Records. The album is made of songs Cash recorded for Sun prior to leaving the label. The album was re-issued in 2003 by Varèse Sarabande with four additional tracks, two of them being alternate versions of songs already on the album.

The tracks on Greatest! were recorded between July 1955 and July 1958. Six out of the twelve songs became singles, with "Get Rhythm" topping the Country charts and becoming the most successful one.