"Twenty Flight Rock" is a song originally performed by Eddie Cochran in the 1956 film comedy The Girl Can't Help It, and released as a single in 1957. The song was published in 1957 as written by Ned Fairchild and Eddie Cochran by American Music Incorporated and Campbell Connelly and Company. Eddie Cochran's contribution was primarily on the music. Cochran's version was rockabilly-flavored, but artists of many genres have covered the song.

The first version of "Twenty Flight Rock" was recorded by Cochran in July 1956 at Goldstar Studio, with Connie Smith on the bull fiddle and Jerry Capehart thumping a soup carton. Cochran re-recorded the song sometime between May to August 1957. This later version was released in the United States (Liberty 55112) with "Cradle Baby" as a flipside. It was a moderate seller, but was more popular in Europe and had steady sales for a long period.

The song follows the twelve-bar blues format, using the device of counting upwards ("One flight, two flight, three flight, four/five, six, seven flight, eight flight, more") in the refrain in a manner similar to "Rock Around the Clock". The lyrics end on a surprisingly morbid note relative to other pop music songs of the time.

The barely 15-year-old Paul McCartney used "Twenty Flight Rock" as his first song when he auditioned for John Lennon on July 6, 1957 in Liverpool, England. The 16-year-old Lennon was impressed by the young McCartney's ability to play the song on the guitar during their first official introductions at St. Peter's Church Hall prior to a church garden fete. The good first impression of McCartney's performance led to an invitation to join The Quarrymen—John Lennon's band that would eventually evolve into The Beatles. On The Beatles Anthology, McCartney noted that: "I think what impressed him most was that I knew all the words."

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