A forty-year-old man named Dmitri Gurov is intrigued by a young woman walking along the seafront of Yalta with her small Pomeranian dog. Dmitri dislikes his shrewish and intelligent wife and, as a result, has numerous love affairs. Although Dmitri disparages women and calls them “the lower race,” he secretly acknowledges that he is more at ease in their company than in men's. One day, “the lady with the dog” sits down next to Dmitri to eat in the public gardens. The man pets her dog in order to strike up a conversation. He learns that she is called Anna Sergeyevna, that she is married, and that she has come to Yalta on vacation. Over the next week, Anna and Dmitri see a lot of each other and grow close. The older man is intrigued by the exuberant naïveté of his young partner, yet he also recognizes a trace of sadness in her character. In contrast to the older women with whom he used to have affairs and who would occasionally display a “rapacious expression" on their beautiful faces, Anna excites Dmitri's desire with her fresh and unaffected nature. In particular, he is drawn by her “diffidence, the angularity of inexperienced youth” that reminds him of his daughter. Every evening the couple observes the sunset from the vantage point over Yalta at Oreanda and are impressed anew by the scenery. The only things that mar Anna's happiness is the thought that her husband, Von Diderits, will send for her and her fear that she has lost Dmitri's respect by sleeping with him. In the end, Von Diderits sends Anna a letter urging her return, and she leaves Dmitri with something like relief. When parting with Dmitri, Anna states, “It's a good thing I am going away...It's fate itself!”

The action switches to describe Dmitri's daily routine in Moscow: visiting his clubs, reading newspapers, and working at his bank. Dmitri believes that his memories of Anna will soon wane and that he can continue his everyday routine in peace and satisfaction. However, this does not happen, and he soon grows to despise the “useless pursuits and conversations” with which he is surrounded. Consequently, Dmitri resolves to visit Anna in her unspecified hometown. The protagonist takes the train to “S—-” and arrives only to pace in front of the Von Diderits' residence, futilely hoping that Anna will emerge and speak with him. When this does not happen, Dmitri decides to go to the theater that evening to see a production of the operetta “The Geisha,” hoping his lover will also attend. Sure enough, he sees Anna in the audience watching the show with her obsequious and insincere-looking husband. When Von Diderits leaves the theater to smoke during the interval, Dmitri approaches Anna and confesses his feelings for her. The young woman tells Dmitri that she has missed him but also berates him for coming to see her. The lovers decide that Anna will visit Dmitri in Moscow, on the excuse that she has to see a gynecologist.

The story concludes with a description of Anna's visits to Moscow and the unbearable strain she feels living this lie. Although Dmitri is perfectly happy with the way things have worked out, he does admit to feeling disconcerted about the implications of falling in love for the first time. He criticizes himself for being an aging, graying old man who seduced women by pretending to be someone he was not. Dmitri comforts Anna as best he can, but he knows that there will be a long way to go before they can be freed from their “intolerable fetters” and live together openly.