Castelvetrano, town, western Sicily, Italy, southeast of Marsala. Historic monuments include the churches of S. Domenico (1470) and of the Madre (16th century). In the town hall there is a 5th-century bronze statue of the Ephebus of Selinus (Selinonte). Castelvetrano serves a wine-producing region and has a furniture industry. Pop. (2006 est.) mun., 30,351.