In a small, colorful hillside town where humans and robots live side by side, a five-year-old robot boy named Astro explores his world with the help of his robot parents, his mentor Dr. OShay, and a group of older human friends. Astro appears to be a normal, playful child, but he possesses incredible strength and the ability to fly. His upbeat and curious nature often leads him and his companions into exciting adventures and new discoveries about the world around them.

The town is also home to a mansion-dwelling criminal named Hamegg, who envies Astros abilities. Along with his two accomplices, the scientist Dr. Flau and a large purple gorilla robot named Gora, Hamegg constantly devises silly and lighthearted schemes to outsmart, outdo, or even impress Astro and his friends. Unlike the more serious villains of previous Astro Boy stories, Hamegg and his cohorts are portrayed as comedic and bumbling. Each episode typically ends with Astro successfully thwarting their plans or the two sides unexpectedly working together.

The series features a cast that includes Astros human friends Ken, an athletic leader; Mitchy, a girl with long purple hair; and Paul. Dr. OShay, a kindly professor, lives in a teapot-shaped house and acts as Astros guide, while Hamegg resides in a pig-shaped castle, with many of his gadgets and settings also following a pig theme. New characters created for this series include Reggie the repairman robot, Pikko the floating teacher robot, and Tac an overeating car robot.

Across its eight episodes, the story follows the groups journeys through various everyday adventures. These range from Astro becoming a racer and going to space to learning about recycling and cleaning. The tone remains consistently jovial and educational, with each installment delivering a positive message suitable for young children. The series is designed as edutainment, focusing on themes of cooperation, curiosity, and learning as Astro and his friends bravely face challenges and discover the worlds values and wonders.