The action takes place in a small village on the Gulf in the Mexican part of California. The protagonist, Kino, a poor pearl catcher, wakes up in his modest reed hut; next to him are his wife Juan and baby Coyotito, sleeping in a drawer suspended from the ceiling. Having fed the child, Juan again puts him in a box. At this moment, to the horror of his parents, the scorpion, walking down the rope, stings the boy. Cinema manages to grab and crush the scorpion, but the poison has already penetrated into the body of the child. Juana is trying to suck out the poison. Neighbors run to the cry of a child: a scorpion bite is very dangerous, and Kino carries the boy to a beautiful house where a white doctor lives. This "fat, lazy man" belongs to the race, which "for almost four centuries beat, starved, and robbed, and despised Kino's fellow tribesmen." Having learned from the servant about the arrival of Kino, the doctor says that he does not want to treat "some Indians" from insect bites. Kino also has no money to pay for a doctor’s appointment, and the servant informs him that the doctor is not at home. Having experienced a sense of shame, the humiliated Kino returns to his hut.

This morning, Kino along with Juana goes to the shore of the Gulf to start catching pearls. He gets into the boat, taking the basket to which the rope is tied; its other end is tied to a stone. This is his primitive, but reliable fishing gear. He heads for the pearl beam. There, on a “rocky bottom dotted with broken open shells, scalloped pearls. It was the same bank that in past centuries elevated the King of Spain to the first place in Europe, the bank that gave him money for waging wars and dressed more than one church with rich robes for the peace of his soul. ” Cinema begins fishing: "youth and pride" allow him to be under water for more than two minutes. He works slowly, choosing the largest shells. Like other representatives of his people, he loves to sing songs. Today he sings the Song of the Underwater World. He used to admire his bizarre beauty. Sings in honor of the pearl, in honor of the very beautiful that suddenly exists. And here he is surprisingly lucky. He sees a large shell, which lies alone, without relatives. Intuitively, he feels that it contains something special. He tears the sink from the bed and rises to the surface. For a long time he does not dare to open this sink. Finally he opens it with a knife. Before him is a huge pearl, not inferior in perfection to the moon itself. “She absorbed the light and seemed to purify it and give out silver radiation. She was big - with the egg of a sea gull. She was the largest in the world. "

Juana's breath takes in joy. Turning her eyes to Coyotito, she notices that her son's edema subsides, that his body is overcome by poison. Filled with happiness, Kino emits a joyful cry.

Meanwhile, the village, likened to a living organism, lives its own life. No sooner had Kino, Juan and other catchers reached the reed huts, when "the nerves of the city tensed and vibrated, receiving the startling message:" Cinema caught the Pearl - the largest in the world. " The news that Kino is fabulously wealthy immediately changes his attitude. Everyone thinks about how he can benefit from this.

Cinema, however, indulges in dreams, for which he will use his wealth: he will marry Hu-ana in the church, buy a brand new sailor suit, and see him sitting at his desk. In the end, the main thing for him, illiterate, depressed by the need and oppression of an Indian, is to give his son an education so that he can "read and write." And the local priest is already hurrying to the poor hut to him and asks for money to be transferred to the church. The white doctor is also: he is ready to treat Coyotito and gives him a medicine, which makes the baby only get worse. During the second visit, he pours some kind of drug into his mouth, after which things are getting better. Thus, he demonstrates his healing power, hoping to get a good reward. Now Kino needs to sell the pearl in order to settle accounts with the doctor.

From early morning, he sets off for this purpose in La Paz, a nearby town, adjacent to the village of pearl-catchers. And this event becomes the public domain: everyone with a greedy, yours is watching him. Now Kino will have to deal with buyers, acting together as a “single one-armed buyer”, whose goal is to deceive, bring down the price as much as possible, get as much profit as possible. One by one, Kino bypasses their offices, where they offer him a very low price for his treasure and, moreover, try to prove that the pearl is not so perfect.

Both Kino and Juan feel the atmosphere of tension begin to thicken around them; they seemed to have entered a new, unexplored strip of existence, completely unusual for them. A targeted hunt for their pearl begins. At night, in the cabin, Kino feels someone's slight movement next to him. Someone entered his home. Juana sees a wound on her husband's face. Who did this is unknown. Juana tells her husband that she is scared, that the pearl is “unkind,” that she must be destroyed before she destroys them herself, offers to throw her into the sea. But Kino resolutely objects. “I will not give up,” he insists. - I will overcome. We will not miss our happiness. ” Tomorrow with the first rays of the sun they will move on.

They go to bed again. Then Juana decides to go to the shore alone and throw the pearl into the sea. Noticing this, Kino rushes after her, seized with anger. At this time, some people hiding in the reed, rush at him, begin to search him. In a battle with the attackers, Kino kills one of them with a knife. Others run away. But they could not take the pearl. Running up Juan found her, dropped from the hands of Kino, on the path. Cinema tells her to quickly run to the hut, grab Coyotito and a little corn to escape from the enemies on the boat. But it turns out that in the boat, well-tarred, its main wealth, the bottom of the Enemy is broken and here they tried to bring him irreparable damage. He hurries home and sees that his hut is in flames. With his wife and child, Kino is hiding in the cabin of Juan Thomas. The whole village is seething, discussing the fire and the disappearance of the Kino family.

At night, with his wife and baby, he secretly leaves the village. Fearful, sweeping tracks through the wind, covering their faces, they move at a brisk pace. No one sees them. Juana has a bag of scarce food on her shoulders, on Coyotito's arms. Finally, they enter a deserted, desolate area, begin to climb the mountains. And here Kino notices people in the distance: two pedestrians and a rider. These are their pursuers: highlanders, by the smallest signs, are able to detect how and where a person is moving. Fearful, the fugitives continue their journey. But the pursuers are confidently following the trail. The sun begins to touch the teeth of granite mountains, and Kino goes to the cleft, where under the rock a stream has formed a small barrel. Exhausted by thirst, Kino and Juan finally quench her, and the mother washes the baby. Having laid Coyotito, Kino watches from a height as the pursuers reached the barrel, leaving the horse somewhere below, and stopped for the night. Two trackers go to bed, the third with a rifle guards. Cinema decides to deal with them. Inaudibly he descends from the top, armed with a knife. At this moment, Coyotito begins to cry. Two rangers begin to discuss this. They think that this is a coyote howl, and decide to "reassure" it. And at the very moment when one of the trackers shoots in the direction of the cave, Kino quickly rushes at him, his knife stabs the enemy in the neck. And at that moment, upstairs from the cave, the heart-rending cry of Juana is heard. Little Coyotito is killed.

... Everyone in La Paz remembers their return. They walk gripped in grief, with a convulsive step, like skillfully made wooden dolls, go to their village, to the black square, which was once their home. Then head to the Gulf. They don’t look at anyone, not even at their broken boat. Cinema holds a pearl in his hand. She is a kind of mirror of what is happening. Much is reflected in it. And she herself is changing. Its surface is gray, bumpy. She is scary, like a malignant tumor. Behind Kino's back stands Juan, holding in his hand his terrible bundle with the body of a dead son. And Kino throws a pearl at sea. Kino and Juan have been standing near for a long time, they keep their eyes on the place where the pearl disappeared.

The final lines of the story are as follows: “... The pearl touched the beautiful green water and went to the bottom. Swaying algae called, beckoned her to him. It played beautiful green highlights. She touched the sandy bottom. Water on the surface of the sea was like a green mirror. And the pearl lay at the bottom, among cirrus, similar to fern plants. The crab, slipping past it, picked up a light cloud of sand behind it, and when it dispersed, the pearl disappeared. And the song of the pearl first turned into a slurred whisper, and then completely fell silent. ”