The story opens during Dmitri Dmitrich Gurov's vacation in Yalta, a seaside resort in Imperial Russia. Nearly forty years old, Gurov is married with three children: a daughter and two sons. He is regularly unfaithful to his wife, however, and when a young woman with a dog appears in Yalta alone, he becomes determined to get to know her. One day when they are both dining at the local restaurant, Gurov strikes up a conversation with her. Together, they leave the restaurant and talk for a few hours walking by the coast. Only then does Gurov find out her name: Anna Sergeyevna. She is married, but when he goes to bed that night, Gurov is sure he would see her the next day.
During the next week, Gurov and Anna spend time together and become lovers. One day, a letter from her husband comes, informing her of problems with his eyes and asking her to return. Gurov and Anna part on the train platform, saying goodbye forever. Gurov then heads home to Moscow, where he rejoins high society life in the city. To his chagrin, however, he cannot get his memories of Anna out of his head. Eventually, he begins to regard Moscow life as shallow and meaningless. He makes haste to the town of S— to find Anna.
In S—, Gurov lurks outside Anna's husband's house in hopes that he will catch a glimpse of her. When he does not, he almost heads back to Moscow in defeat, but he decides to see a production of "The Geisha" at the theater before doing so. At the play, Gurov finds Anna in the third row. She is horrified by seeing him—not because she does not love him, but rather because she is afraid of seeing him in public with her husband. She tells him to leave and promises that she will visit him in Moscow.
Anna begins going to Moscow every few months, under the pretext of visiting a doctor there. She and Gurov meet at the Slavyanski Bazaar hotel. On the way to one such rendezvous, Gurov walks his daughter to school, excitedly telling her about snow and the atmosphere as he imagines his visit with Anna. Later, at the hotel, Anna begins crying because she cannot bear keeping their love private. The narrator describes their love as something beautiful and tender. Gurov is suddenly struck by his advancing age and the irony of finally having fallen in love so late in life. The two lovers talk about what they can do to be together, despite being married to other people. The story ends as they continue the search for a solution.