十二年前離開地球的二百九十六名地球人，因太空船意外被逼降落於出雲星。當中第一對步出逃生艙的夫婦，誕下一位男嬰，並取名為大和武尊。故事便從定居於出雲村的武尊在偶然下喚醒沉睡的魔空戰神須佐尊，從此踏上尋找八個行星之魂所在地，以解救出雲星被毀源的危機。

地球人为寻觅新天地，于公元二十五世纪移居“出云星”，其中大和夫妇生下男婴，取名武尊。一日，武尊无意中唤醒了沉睡百万年的机械战士，机械战士名叫“须助尊”，本为魔彗星统治者“月夜见”八大魔天战士中实力最强的战士，但在一次意外中，须助尊因失控而失踪了……

우주선에서 태어난 소년 야마토 타케루의 모험을 그린 로봇 애니메이션

In the 25th century, a spaceship carrying 300 people leaves the earth in search of a new world in the solar system, but an unexpected accident occurs. They crash into a black hole which is connected to another universe. The people on the ship are cast adrift in an emergency capsule to a planet called Ismo. The story begins 12 years after they have reached Ismo.

Ismo is a star of the Onam System, which corresponds to the Solar System in our universe. It is the only planet left in the Onam System. The Death Star called Yomi is a comet which regularly approaches the Onam System.