Mnesicles (5th century BCE) was the architect of the great Propylaea of the Athenian Acropolis, set up by Pericles about 437 BCE. The Erechtheum is also sometimes ascribed to him. Also spelled Mnesikles Greek architect known (from Plutarch) to have been the designer of the Propylaea, or the entrance gateway to the Acropolis at Athens.

The only entranceway to the Acropolis at its western end, the Propylaea, was built of Pentelic marble, with some details of black Eleusinian stone. He created a powerful, unique, and beloved masterwork of the Ionic style. Construction was begun in 437 BC but was halted in 431 BC with the outbreak of the Peloponnesian war.