Castel San Giorgio (Campanian: Sangiorge) is a town and comune in the province of Salerno in the Campania region of south-western Italy.

[1] The town, founded in 1810 and located near the site of the ancient Nuceria Alfaterna, was originally named San Giorgio, until 1861.

The municipality borders with Mercato San Severino, Nocera Inferiore, Roccapiemonte, Sarno and Siano.

[4] It counts eleven hamlets (frazioni): Aiello, Campomanfoli, Castelluccio, Cortedomini, Fimiani, Lanzara (the most populated one), Santa Croce, Santa Maria a Favore, Taverna-Casalnuovo, Torello and Trivio Codola (also named Codola).

It is also served by the motorway A30 Salerno-Caserta, at the exit "Castel San Giorgio".