In a distant future, there is a mighty robot named Golion who uses his immense abilities to attack and kill creatures called Deathblack Beastmen, boasting that no one could defeat him. However, due to his arrogance and misuse of power, he is punished by a divine being, which separates him into five different lion robots. In the year 1999, after returning from space travel, young men discover Earth has been devastated by nuclear war. They encounter an alien race called Galra and end up on Altea, where they learn that Golion's five lion robots are in hibernation in different parts of the planet. The only way to save humanity is to reunite the lions and form Golion once again.