Senku Ishigami is the brilliant, sharp-tongued protagonist driving the revival of humanity. Armed with an absolute, encyclopedic memory of human history, physics, chemistry, and engineering, he views the petrified world not as a tragedy, but as a massive scientific puzzle. Senku is intensely pragmatic, often masking his deep empathy with a cold, logical, and slightly "mad scientist" persona. He operates on a strict meritocracy of intellect and effort, completely unbothered by social status or physical strength. His catchphrases, like "One billion percent," reflect his unwavering confidence in the laws of nature. Senku is not a physical fighter; his true weapon is his brain, which allows him to systematically reverse-engineer modern civilization from dirt, rocks, and raw minerals.

Taiju Oki is Senku’s childhood friend and the ultimate physical engine of the Kingdom of Science. Unlike Senku, Taiju possesses zero scientific aptitude, but he compensates with an astronomical level of physical endurance, stamina, and loyalty. He is a strict pacifist who refuses to hit another human being, channeling his immense strength entirely into defense, manual labor, farming, and resource gathering. Taiju’s unwavering trust in Senku’s intellect forms the emotional bedrock of their partnership; he will happily perform backbreaking labor for days without question if Senku says it will benefit their goals. His simple-minded, honest nature makes him the perfect emotional anchor for the group.

Yuzuriha Ogawa is a cheerful, deeply compassionate girl who completes the original childhood trio alongside Senku and Taiju. Behind her quiet and gentle demeanor lies an incredible, unparalleled talent for handicrafts, textiles, and intricate reconstruction. Yuzuriha plays a critical, top-secret role in the reconstruction of humanity by meticulously piecing together the shattered fragments of petrified humans, ensuring they can be safely revived without missing limbs or scars. Her immense patience, steady hands, and emotional resilience allow her to execute high-stakes espionage and delicate crafting tasks that require surgical precision, making her indispensable to the rebirth of society.

Kohaku is a fierce, agile, and exceptionally strong young woman from Ishigami Village who becomes Senku’s first true ally in the Stone World. Possessing eyesight that matches a bird of prey and physical reflexes that rival top-tier modern athletes, she serves as the primary muscle and military commander of the Kingdom of Science. Kohaku is deeply noble and protective, initially aligning with Senku because she recognized his selfless desire to save others. While she often teases Senku for his manipulative tendencies, she respects his intellect deeply and willingly risks her life on dangerous stealth missions, combat engagements, and exploration scouts to secure his safety.

Chrome is a young man from Ishigami Village who initially considers himself a "sorcerer" due to his habit of collecting unique minerals and experimenting with basic chemical reactions. Upon meeting Senku, Chrome’s worldview explodes as he realizes his "sorcery" is actually the foundation of science. He quickly becomes Senku’s enthusiastic apprentice and closest intellectual equal in the primitive world. Chrome possesses an innate curiosity, a sharp analytical mind, and a unique ability to think outside the box, often coming up with unorthodox, brilliant solutions that complement Senku's structured, modern knowledge. His journey represents the organic rebirth of human curiosity.

Gen Asagiri is a flamboyant, cynical, and highly intelligent mentalist and psychologist who was revived from the modern era. Originally sent as a spy by an enemy faction to assess Senku, Gen quickly defects to the Kingdom of Science after witnessing Senku's ability to create a working generator and promising him a simple bottle of cola. Gen specializes in human psychology, linguistic manipulation, negotiation, and strategic deception. He acts as the ultimate diplomat, smooth-talking rival factions, boosting ally morale, and managing social engineering. Despite his self-proclaimed sleazy and cowardly nature, Gen is fiercely loyal to Senku and consistently protects the group from behind the scenes.

An elderly, muscular artisan who spent his life crafting primitive tools. Senku's blueprints ignite his passion, allowing him to flawlessly forge modern glassware, vacuum tubes, and engines, bridging theory and reality.

A tiny village girl who wears a melon helmet to fix her blurry eyesight. After Senku gives her glass lenses, her fierce loyalty makes her the ultimate stealth scout, rolling inside her shell to spy on enemies undetected.

A revived billionaire heir and genius navigator who wants to own the oceans. His intense greed drives human progress, as he introduces currency, capitalism, and hot air balloons to help Senku harvest global resources.