The Ascoli Piceno Baptistery (Italian: Il battistero di San Giovanni di Ascoli Piceno), also known as the baptistery of Saint John, is a religious building found on the eastern end of the piazza Arringo at the center of Ascoli Piceno and sitting next to and just north of the cathedral dedicated to St. Emygdius, the city's patron saint.
The structure, simple and austere in its architectural form, perfectly represents the Romanesque style in Ascoli, and, being ranked among the best examples of Italian works of art, is included in the list of Italian national monuments (r.d. n.7033 del 20/07/1890).