Launched on January 19, 1965, atop a Titan II rocket, Gemini 2 was the last unmanned test flight for the Gemini Program. The suborbital flight lasted 18 minutes and was a success. The spacecraft was subsequently re-flown as a test for the "Gemini B" spacecraft for the military Manned Orbiting Laboratory (MOL) program, probably the first-ever reuse of a reentry vehicle and a manned-type spacecraft. Launched November 3, 1966, aboard a Titan IIIC rocket, the spacecraft completed a suborbital trajectory, successfully testing the circular hatch cut into the heat shield, which was to be the configuration to be used in the MOL program so that the military astronauts could transfer to the attached laboratory module. The MOL program was cancelled in 1969 before any manned reconnaissance missions were ever flown.

In 1968 NASA transferred Gemini 2 to the Smithsonian Institution, as it was no longer needed for MOL.