Pietraporzio is a comune (municipality) in the Province of Cuneo in the Italian region Piedmont, located in the Valle Stura about 100 kilometres (62 mi) southwest of Turin and about 40 kilometres (25 mi) west of Cuneo, on the border with France.

Pietraporzio borders the following municipalities: Argentera, Canosio, Saint-Etienne-de-Tinée (France), Sambuco, and Vinadio.