Alcestis is an Athenian tragedy by the ancient Greek playwright Euripides. It was first produced at the City Dionysia festival in 438 BC. Euripides presented it as the final part of a tetralogy of unconnected plays in the competition of tragedies, for which he won second prize; this arrangement was exceptional, as the fourth part was normally a satyr play. Its ambiguous, tragicomic tone—which may be "cheerfully romantic" or "bitterly ironic"—has earned it the label of a "problem play." Alcestis is, possibly excepting the Rhesus, the oldest surviving work by Euripides, although at the time of its first performance he had been producing plays for 17 years.

Euripides was a tragedian of classical Athens. Along with Aeschylus and Sophocles, he is one of the three ancient Greek tragedians for whom any plays have survived in full. Some ancient scholars attributed ninety-five plays to him, but the Suda says it was ninety-two at most. Of these, eighteen or nineteen have survived more or less complete. There are many fragments of most of his other plays. More of his plays have survived intact than those of Aeschylus and Sophocles together, partly because his popularity grew as theirs declined—he became, in the Hellenistic Age, a cornerstone of ancient literary education, along with Homer, Demosthenes, and Menander.