Petrovija is located in the City of Umag, in Istra County at an elevation of 41 meters above sea level and it covers the area of 4.99 km² (1.93 sq. miles). According to the 2011 census report, there were 471 inhabitants. It is mostly populated by Croats (63%), but also Italians (30%). Nearby places: Finida, Vilanija, Seget, Čepljani, Vardica, Juricani, Kmeti, Sveta Marija na Krasu, Đuba and Križine.