3000 years ago, in a distant corner of the universe, there was a green planet called Venus with an environment similar to Earth. However, Venus was destroyed by the Satan Empire, which invaded only green planets to seize their territories. Just before the explosion, the seventh princess of Venus, Ledia, sent the DNA and regeneration device of the Vector Man warriors to Earth. Meanwhile, the Satan Empire, after destroying Venus, set Earth as its next target and began the invasion under the command of Commander-in-Chief Medusa. Princess Ledia found three young men on Earth (Tiger, Eagle, and Bear), awakened them as Vector Man warriors, and they fought against the Satan Empire for the peace of Earth.