Senku Ishigami A science-loving boy at heart with a superhuman brain, vast knowledge, and a strong spirit of inquiry. He aims to restore civilization from zero using the power of science in the Stone World. While he has a cool and rational way of thinking, he has a strong, passionate love for his friends. His catchphrase is "This is exhilarating."

Ukyo Saionji Trusted as a brain of the Kingdom of Science for his incredible hearing and insight that allows him to sense danger. Before petrification, he was a member of the Self-Defense Forces and a submarine sonarman, so he is entrusted as the sonarman of the Perseus. His skills with a bow and arrow are also top-notch. He can speak English.

Kohaku A girl with blonde hair and blue eyes. Possessing light movements and high experience, her combat power is second to none, even among men. She speaks in an archaic manner. She took a liking to Senku's way of life, and after her sister Ruri overcame her illness thanks to the sulfa drug, she continues to lend her strength to Senku as a member of the Kingdom of Science.

Suika She always wants to be useful to everyone and has a very hardworking personality.

Kaseki The most skilled craftsman in Ishigami Village, having devoted 50 years solely to making things. With high crafting abilities and a sturdy physique, he is the central figure for manufacturing in the Kingdom of Science, handling even difficult crafts single-handedly. When he gets excited, his muscles swell up and his clothes burst off.

Hyoga A spearman revived from petrification by Tsukasa, he was effectively the number two of the Tsukasa Empire. He wields a special spear called a Kudayari and boasts overwhelming combat power comparable to Tsukasa. He has a cold and ruthless personality, choosing any means necessary to achieve his goals.

Tsukasa Shishio The strongest high school primate. A man with terrifying combat power who can defeat a lion with his bare hands. He is always calm and intellectual. Believing that an ideal world without vested interests should be created using only pure-hearted youths, he built the Tsukasa Empire by reviving only those he chose and clashed with the Kingdom of Science, but he is now an ally fighting alongside them.

Gen Asagiri A magician and mentalist revived from petrification by Tsukasa. He speaks flippantly with a light, airy tone and uses his extraordinary speaking skills to manipulate others. He is also skilled at vocal mimicry. He first appeared in Ishigami Village as Tsukasa's spy, but he gradually became attracted to Senku's power to build civilization and joined the Kingdom of Science.

Ryusui Nanami The scion of the Nanami Conglomerate shipping company, possessing a grand scale and excellent leadership. He boasts outstanding sailing skills and has been handling sailing ships since middle school. He is greedy enough to be called the "greediest man in the world," but he also has the side of a stoic hard worker who never compromises on his desires. His trademarks are a large captain's hat and a red captain's coat. His catchphrase is "I want it!"

Chrome Curious, clever, and straightforward. He used to collect various materials in an attempt to cure Ruri's illness. After meeting Senku, he became fascinated by science and is now a member of the Kingdom of Science, striving to master science together. A flexible thinker, he is a science user who sometimes surprises even Senku.