Alfredo and Violetta Valéry are now living happily in a country villa. Alfredo discovers from the maid Annina that Violetta is selling her jewels because she has run out of money and rushes to Paris to get some.
Violetta, having refused an invitation to one of Flora's parties, receives an unexpected visit from Alfredo's father, Giorgio Germont, who accuses her of leading his son into poverty. Violetta replies that she has never asked Alfredo for anything, but Giorgio does not give up his plan to separate Alfredo and Violetta. Violetta does what she believes to be the best for her lover and abandons Alfredo, who is overcome with jealousy.
Violetta reappears at a party, again accompanied by Duphol, who would like to challenge the young Germont to a duel, Violetta begs him to leave the house; he will leave, he says, only if she follows him. Violetta reveals that she has sworn to Duphol that she will never meet him again, so as not to tell Alfredo about the conversation she had with her father. Giorgio arrives and reproaches him for this behaviour, but does not reveal the truth.
Violetta's health has deteriorated. She can no longer get up from her bed. She receives a letter from Germont: at last he has decided to explain everything to his son. Alfredo is moved and is on his way.
Violetta is incredibly happy, but fears she will not survive until he arrives. But finally Alfredo is there, at her bedside, and his deeply regretful father is also there. La tisi uccide Violetta davanti a loro, in un clima di acuto dolore, addolcito però dalla delicatezza e dalla purezza dei sentimenti.