Kino is a hard-working pearl-diver and the protagonist of the novella. He has a wife, Juana, and a son, Coyotito. He is content with his lifestyle as a diver and possesses nothing of value until he discovers the pearl. After finding the pearl, Kino gradually changes to become a completely different man. Though his family is still the center of his actions, he is also driven by his dreams of an escape from their poverty and a desire to give his son a better future. He quickly becomes obsessed with the material things that the pearl could bring. He is no longer content with his son being uneducated, or his family not being well-dressed. Instead of enjoying his family and their company, as he did in the beginning, he becomes discontent and always seeks more.[10] He is also driven by his desire not to be cheated or slighted. Kino is named for the missionary Eusebio Kino.[11]
Juana, Kino’s wife, is a secondary character. She is a loving woman who cares for her husband and son. Throughout the experience, she remains loyal to her family but also perceives the evil forces that the valuable pearl attracts. For example, two nights after the pearl is found, she attempts to throw it back into the ocean to bring back peace and happiness to her family.[9]
Coyotito is Juana and Kino’s infant son. He is their only child, and his parents do everything they can to protect him. Despite his parents’ love and effort, he is subject to much harm, both before and after the pearl is found. Coyotito is shot and killed by one of the pearl hunters.
The Doctor, unnamed in the novella, is a symbol of wealth, greed and exploitation. He is repulsive, fat, and also foreign-born, a native of France. Before the pearl is found, he refuses to heal Coyotito because the family is poor, though it would be easy for him to do so. After Kino finds the pearl, he personally visits the family at home, acting much friendlier than at their first meeting and even pretending to heal Coyotito's scorpion sting with ammonia. During the doctor's visit, he tries to determine from Kino's glances where in the house the pearl may be hidden, though Kino is too suspicious to reveal anything. The doctor's behavioral changes foreshadow the more serious troubles that begin after Kino's discovery of the pearl.
Juan Tomas, Kino’s brother, is wise and loyal. He is the only other character in the book to suspect the manipulation undertaken by the pearl dealers. When destruction does come, Juan Tomas does not turn away his brother but, instead, welcomes him in and protects him. He is one of the few characters that does not seek to gain from the pearl and shows he values the importance of family ties.
Apolonia is the wife of Juan Tomas who helps his brother in protecting and hiding Kino.
The pearl dealers, like the doctor, symbolize the exploitation of the native population, this time by the organized pearl-dealing cartel for which the dealers work. When Kino tries to sell the pearl, the pearl dealers claim that the pearl's size makes it worthless and offer Kino a fraction of the pearl's true worth. Kino's outrage at their barehanded lies causes him to brave the dangerous trip to the capital and seek a better price.[12]
The thieves and trackers are shadowy figures who attack Kino from the first night he has the pearl. Kino never recognizes who they are. They harass and then follow the family right to the end of the story. They force Kino to fight and kill to defend himself and his family and keep the pearl his own. In the final scenes, in which Kino is tracked by a posse, it is not clear in the text whether the group are thieves or law enforcement officers hunting Kino for his killing of the man on the beach.
