In the year 2194, mysterious beings, known as the Gamilons, suddenly appear from outer space. The Gamilons drops meteor bombs upon Earth and kill most of the inhabitants. Five years later, in 2199, the Earth is still contaminated by radiation from the meteor bombs. Those that remain live underground.
Susumu Kodai (Takuya Kimura) is a former army pilot now retired. One day, while exploring the surface, he comes across a communication capsule from planet Iscandar, which resides 148,000 light years away from Earth. Susumu Kodai is able to ascertain that on Iscandar they have a substance to remove the radioactive material plaguing the surface of Earth.
In order to retrieve the substance from Iscandar, the Defense Force of Earth builds Space Battleship Yamato. Susume Kodai comes out of retirement and leads the crew that will man Space Battleship Yamato. With only one year left before the radiation drives Earth to complete extinction, Susume Kodai and his crew begins their great battle...