Cava de' Tirreni (Italian: [ˈkaːva de tirˈrɛːni]; Cilentan: A Càva) is a city and comune in the region of Campania, Italy, in the province of Salerno, 10 kilometres (6 miles) northwest of the town of Salerno. It lies in a richly cultivated valley surrounded by wooded hills, and is a popular tourist resort. The abbey of La Trinità della Cava is located there.

Cava de' Tirreni lies among the hills close to the Tyrrhenian Sea, 5 km (3 mi) north of the Amalfi Coast and serving in practice as its northern gateway. The inhabited area is 198 m above sea level, in a valley situated between two mountain groups: the Lattari Mountains (which separate Cava from the Amalfi Coast) to the west and the Picentini Mountains to the east.

Cava is bordered to the north by Nocera Superiore, Roccapiemonte and Mercato San Severino; to the east by Baronissi, Pellezzano and Salerno; to the south by Vietri sul Mare and Maiori; and to the west by Tramonti.^{[citation needed]}

The Italian: frazioni of Cava are: Alessia, Annunziata, Arcara, Casaburi-Rotolo, Castagneto, Corpo di Cava, Croce, Dupino, Marini, Passiano, Pregiato, San Cesareo, San Pietro, Sant'Anna, Sant'Arcangelo, San Martino, Santa Lucia, Santa Maria del Rovo, Santi Quaranta.

The town, initially comprehending present-day Vietri sul Mare, was founded by the Etruscans with the name of Marcina, as part of a colonial system known as Etruria Campana. The modern name Cava de' Tirreni (lit. 'Cave of the Tyrrhenians') is a tribute to the Etruscan heritage of the area. The church and the greater part of the abbey buildings were entirely modernized in 1796. The old Gothic cloisters are preserved. The church contains a fine organ and several ancient sarcophagi. The archives, now national property, include fine incunabula, documents and manuscripts of great value (including the Codex Legum Longobardorum of 1004 and the La Cava Bible).

Cava de' Tirreni is twinned with: