Jim is the 17-year-old son of an innkeeper in a small English coastal town. Following his father's passing and the discovery of a pirate's map, he secures a position as the cabin boy aboard the Hispaniola. He is highly observant and acts with courage when facing dangerous adults. His independent streak occasionally leads him to leave his designated posts in pursuit of strategic advantages for his friends.

Hired as the sea cook for the Hispaniola, Silver is a charismatic mariner missing his left leg. He runs a tavern in Bristol and keeps a pet parrot named Cap'n Flint. Beneath his jolly, helpful exterior lies a highly intelligent, ruthless pirate leader. He uses flattery and shifting loyalties to maneuver for control over the expedition's treasure, making him a dangerous adversary.

The hired captain of the Hispaniola, Smollett is a strict and highly organized leader. He values order, duty, and straightforwardness, which initially earns him the dislike of the more relaxed crew members. His cautious foresight regarding the ship's security quickly proves justified as the voyage progresses. He insists on flying the British flag even when it draws enemy fire, demonstrating his unyielding sense of honor.

A neat, intelligent physician and local magistrate with a calm demeanor. He treats Jim's sick father and is entirely unbothered by the aggression of the pirates who visit the inn. He serves as one of the primary leaders of the honest men's expedition. Hardworking and dedicated to his profession, he maintains his medical ethics even when treating enemy combatants.

A tall, broad landowner with a rough face and a quick temper. He provides the financial backing to outfit the Hispaniola and hire its crew. Though honest and well-meaning, he is talkative, easily excited by the prospect of immense wealth, and overly trusting of charismatic strangers. His financial resources make the voyage possible, but his lack of discretion creates early risks.

A ragged, sunburnt former pirate marooned on Treasure Island three years prior to the Hispaniola's arrival. Having survived entirely on goats, berries, and oysters, his isolation has left him eccentric. He possesses crucial knowledge about the island's terrain and the buried gold, making him a valuable but unpredictable asset to the honest men.

A tall, heavy sailor with dirty fingernails and a distinctive saber cut across one cheek. He is a rough, secretive lodger at the Admiral Benbow Inn who drinks excessive amounts of rum. He pays Jim a silver fourpenny to watch for a one-legged seafaring man. His mysterious past and the sealed map in his sea chest set the entire adventure into motion.

The cockswain aboard the Hispaniola and one of Long John Silver's closest confidants. He is a dangerous, impatient pirate who favors immediate violence over strategic planning. He plays a key role in the mutineers' maneuvers to control the ship and engages in a tense, violent standoff with Jim.

The co-owner of the Admiral Benbow Inn. She is a practical, honest woman who refuses to take more than her rightful due from the dead sea captain's chest. She protects her son and business as best she can when pirates ransack their home.

The sickly innkeeper of the Admiral Benbow. His declining health brings Dr. Livesey to the inn, and his subsequent passing leaves Jim and his mother to manage the dangerous lodger alone.

A pale pirate missing two fingers on his left hand. He tracks down The Old Sea Captain at the inn, resulting in a violent duel. He serves as the first indication that the captain's past has finally caught up with him.

A dreadful-looking blind pirate who wears a sea cloak with a hood. He delivers a terrifying summons known as the black spot to The Old Sea Captain. His cruel grip and threatening demeanor make a lasting impression on Jim.

A local supervisor who helps rescue Jim and his mother from Blind Pew's gang. He escorts Jim to see Dr. Livesey and Squire Trelawney, acting as a crucial link to local law enforcement.

The squire's dependable estate worker. He acts as a guard for Jim before the voyage and serves as a loyal watchman for the honest men on the island. He carries out his duties without complaint.

The mate of the Hispaniola. He is an old sailor with earrings and a squint who drinks heavily while on duty. Captain Smollett quickly identifies him as too familiar with the crew and incapable of maintaining authority.

The boatswain aboard the Hispaniola who takes on extra leadership duties early in the voyage. He is physically imposing and actively participates in the mutineers' violent assault on the stockade.

A seemingly undecided crewman aboard the Hispaniola. When given a final chance to abandon the mutiny, he steps away from the pirates to follow Captain Smollett's orders, proving his underlying integrity.

An impatient mutineer who attempts to usurp Silver's position as captain. He is eager to attack the honest men and claim the treasure without waiting for a strategic advantage, causing friction within the pirate ranks.

A notoriously bloodthirsty pirate captain who buried a vast fortune before his death. Though no longer living, his legacy of violence and hidden wealth drives the actions of nearly every character in the story.

A green parrot belonging to Long John Silver, named in honor of the notorious deceased pirate. She is a constant companion to the sea cook and adds a layer of noisy unpredictability to his presence.