Chiesa di Sant'Agata la Vetere, Catholic church in San Biagio district, Catania, Italy.

Chiesa di Sant'Agata la Vetere has a sober late-Baroque facade of white limestone framed by pilasters, with a heavy portal topped by a broken-arch pediment and a large central window. The single nave is plain and linear. Near the entrance, a glass case holds the wooden casket that carried Agatha's remains for over 500 years.

The building served as Catania's first cathedral from the 4th century until 1094, marking the beginning of organized Christian worship in the region. It was reconstructed after the 1693 earthquake and rebuilt higher than its original position.

The name "la Vetere" means "the ancient", given after 1094 when Bishop Ansgerio moved the cathedral seat to the new Norman cathedral. During the solemn Agatha festivities, an urn with the saint's reclining body is placed in the Chapel of Sant'Agata, where a 1851 painting by Antonio Pennisi shows her martyrdom.

The church faces Piazza Sant'Agata la Vetere, off Via Santa Maddalena, a short walk east of Piazza Stesicoro and the Anfiteatro Romano. The entrance is on the piazza side; the single nave and the display case with Agatha's wooden casket are seen from inside. It is an active parish church, so visits fit around Mass times.

The wooden chest that held Saint Agatha's relics for over 500 years is kept in a glass case near the entrance. The church also holds a marble sarcophagus with Roman and Byzantine additions, now used as an altar, and the 1854 mausoleum of historian Mario Musumeci by Antonio Calì.