The narrator explains that, as a young boy, he once drew a picture of a boa constrictor with an elephant digesting in its stomach; however, every adult who saw the picture would mistakenly interpret it as a drawing of a hat. Whenever the narrator would try to correct this confusion, he was ultimately advised to set aside drawing and take up a more practical or mature hobby. The narrator laments the lack of creative understanding displayed by adults.
Now an adult himself, the narrator has become a pilot, and, one day, his plane crashes in the Sahara desert, far from civilization. Here, the narrator is suddenly greeted by a young boy or small man whom he refers to as "the little prince". The little prince asks the narrator to draw a sheep. The narrator first shows him his old picture of the elephant inside the snake, which, to the narrator's surprise, the prince interprets correctly. After a few failed attempts at drawing a good-looking sheep, the narrator simply draws a box in his frustration, claiming that the box holds a sheep inside. Again, to the narrator's surprise, the prince exclaims that this is exactly the picture he wanted. The narrator says that the prince has a strange habit of avoiding directly answering any of the narrator's questions. The prince is described as having golden hair, a scarf, and a lovable laugh.
Over the course of eight days stranded in the desert, as the narrator attempts to repair his plane, the little prince recounts the story of his life. The prince begins by describing life on his tiny home planet: in effect, an asteroid the size of a house (which the narrator believes to be the one known as B-612). The asteroid's most prominent features are three minuscule volcanoes (two active, and one dormant or extinct) as well as a variety of plants. The prince describes spending his earlier days cleaning the volcanoes and weeding out certain unwanted seeds and sprigs that infest his planet's soil; in particular, pulling out baobab trees that are constantly trying to grow and overrun the surface. The prince appears to want a sheep to eat such undesirable plants, until the narrator informs him that a sheep will even eat roses with thorns. Upon hearing this, the prince tells of his love for a mysterious rose that suddenly began growing on the asteroid's surface some time ago. The prince says he nourished the rose and listened to her when she told him to make a screen or glass globe to protect her from the cold wind. Although the prince fell in love with the rose, he also began to feel that she was taking advantage of him, and he resolved to leave the planet to explore the rest of the universe. Although the rose finally apologized for her vanity, and the two reconciled, she encouraged him to go ahead with his journey and so he traveled onward.
The prince has since visited six other asteroids, each of which was inhabited by a foolish, narrow-minded adult, including: a king with no subjects; a conceited man, who believed himself the most admirable person on his otherwise uninhabited planet; a drunkard who drank to forget the shame of being a drunkard; a businessman who endlessly counted the stars and absurdly claimed to own them all; a lamplighter who mindlessly extinguished and relighted a lamp every single minute; and an elderly geographer, so wrapped up in theory that he never actually explored the world that he claimed to be mapping. When the geographer asked the prince to describe his home, the prince mentioned the rose, and the geographer explained that he does not record "ephemeral" things, such as roses. The prince was shocked and hurt by this revelation, since the rose was of great importance to him on a personal level. The geographer recommended that the prince next visit the planet Earth.
On Earth, the prince landed in the desert, leading him to believe that Earth was uninhabited. He then met a yellow snake that claimed to have the power to return him to his home, if he ever wished to return. The prince next met a desert flower, who told him that she had only seen a handful of men in this part of the world and that they had no roots, letting the wind blow them around and living hard lives. After climbing the highest mountain he had ever seen, the prince hoped to see the whole of Earth, thus finding the people; however, he saw only the enormous, desolate landscape. When the prince called out, his echo answered him, which he interpreted as the mocking voices of others. Eventually, the prince encountered a whole row of rosebushes, becoming downcast at having once thought that his own rose was unique. He began to feel that he was not a great prince at all, as his planet contained only three tiny volcanoes and a flower that he now thought of as common. He lay down in the grass and wept, until a fox came along. The fox desired to be tamed and explained to the prince that his rose really was indeed unique and special, because she was the object of the prince's love. The fox also explained that, in a way, the prince had tamed the rose, and that this is why the prince was now feeling so responsible for her. The prince then took time to tame the fox, though the two ultimately parted ways, teary-eyed. The prince next came across a railway switchman, who told him how passengers constantly rushed from one place to another aboard trains, never satisfied with where they were and not knowing what they were after; only the children among them ever bothered to look out the windows. A merchant then talked to the prince about his product, a pill that eliminated thirst, which was very popular, saving people fifty-three minutes a week. The prince replied that he would instead gladly use that extra time to go around finding fresh water.
Back in the present moment, it is the eighth day after the narrator's plane-crash and the narrator is dying of thirst; fortunately, he and the prince together find a well. The narrator later finds the prince talking to the snake, discussing his return home and eager to see his rose again, who he worries has been left to fend for herself. The prince bids an emotional farewell to the narrator and states that if it looks as though he has died, it is only because his body was too heavy to take with him to his planet. The prince warns the narrator not to watch him leave, as it will make him upset. The narrator, realizing what will happen, refuses to leave the prince's side; the prince consoles the narrator by saying that he only need look at the stars to think of the prince's lovable laughter, and that it will seem as if all the stars are laughing. The prince then walks away from the narrator and allows the snake to bite him, falling without making a sound.
The next morning, the narrator tries to look for the prince, but is unable to find his body. The story ends with the narrator's drawing of the landscape where the prince and the narrator met and where the snake took the prince's life. The narrator requests that anyone in that area encountering a small man who refuses to answer questions should contact the narrator immediately.