Why does Othello kill himself?

Othello kills himself because he realizes he has murdered the innocent Desdemona after being deceived by Iago, and he sees suicide as both punishment for his crime and a final attempt to recover his lost honor.

The discovery comes too late. After Othello smothers Desdemona to death, Emilia exposes the truth: Desdemona was faithful, the handkerchief was not proof of adultery, and Iago had engineered the deception. Othello had trusted “honest, honest Iago,” but Emilia reveals that she found the handkerchief and gave it to Iago, allowing him to plant the false evidence that destroyed Othello’s judgment. Once letters found on Roderigo’s body confirm Iago’s plots, Othello understands that he killed his wife due to an illusion, and he takes his own life.

His suicide is also tied to public disgrace. Lodovico tells him he must give up his command and return to Venice. Othello had built his identity on military honor and service to Venice, so the loss of that identity deepens his collapse. In his final speech, he asks the others to “speak of me as I am” and describes himself as one who “loved not wisely, but too well.” He admits that he threw away something priceless when he killed Desdemona, comparing her to a pearl richer than anything he possessed.

His final story about killing a “circumcised dog” who attacked a Venetian shows the conflicted meaning of his death. Othello casts himself as a loyal defender of Venice, but as he tells the story of stabbing the enemy, he stabs himself. In that gesture, he treats himself as the criminal who must be executed. His death is an act of remorse, self-punishment, and a desperate effort to control how he will be remembered.

The suicide completes the play’s pattern in which jealousy destroys Othello’s ability to distinguish appearance from reality. By the time he sees the truth, the only form of justice he can imagine is to turn the violence he used against Desdemona back on himself.