San Pietro al Natisone is a comune located in the Friuli-Venezia Giulia region of northeastern Italy. It falls within the regional decentralization entity of Udine and is situated approximately 20 kilometres northeast of Udine and 60 kilometres northwest of Trieste.
The municipality borders several other towns, including Cividale del Friuli, San Leonardo, Savogna, Prepotto, Pulfero, and Torreano. Historically, the town was known by the official Italian name San Pietro degli Slavi, which translates to "Saint Peter of the Slavs," until it was renamed in 1878.