The Juno I was a four-stage American space launch vehicle, used to launch lightweight payloads into low Earth orbit. The launch vehicle was used between January 1958 to December 1959. The launch vehicle is a member of the Redstone launch vehicle family, and was derived from the Jupiter-C sounding rocket. It is commonly confused with the Juno II launch vehicle, which was derived from the PGM-19 Jupiter medium-range ballistic missile. In 1958, a Juno I launch vehicle was used to launch America's first satellite, Explorer 1.

The Redstone family of rockets consisted of a number of American ballistic missiles, sounding rockets and expendable launch vehicles operational during the 1950s and 1960s. The first member of the Redstone family was the PGM-11 Redstone missile, from which all subsequent variations of the Redstone were derived. The Juno 1 version of the Redstone launched Explorer 1, the first U.S. orbital satellite in 1958 and the Mercury-Redstone variation carried the first two U.S. astronauts into space in 1961. The rocket was named for the Redstone Arsenal in Huntsville, Alabama where it was developed.