In Shakespeare studies, the problem plays are plays written by William Shakespeare which are characterized by their complex and ambiguous tone, which shifts violently between more straightforward comic material and dark, psychological drama. Shakespeare's problem plays eschew the traditional trappings of both comedy and tragedy, and are sometimes cited as early predecessors to the tragicomedy.

The term was coined by critic F. S. Boas in Shakespeare and his Predecessors (1896). Boas' use of the phrase was derived from a type of drama that was popular at the time of his writing, most commonly associated with the Norwegian playwright Henrik Ibsen. In these problem plays, the situation faced by the protagonist is put forward by the author as a representative instance of a contemporary social problem. The term can refer to the subject matter of the play, or to a classification "problem" with the plays themselves.

As Boas used it, the term "problem play" was originally used to refer exclusively to three plays that Shakespeare wrote between the late 1590s and the first years of the seventeenth century: All's Well That Ends Well, Measure for Measure, and Troilus and Cressida. Some critics include other plays that were not enumerated by Boas, most commonly The Winter's Tale, Timon of Athens, and The Merchant of Venice. The term has been variously applied to other odd plays from different points in Shakespeare's career, as the notion of a problem play remains somewhat vaguely defined, and its use as a classification is still not accepted by all Shakespeare critics.