Poggio Mirteto is a comune (municipality) and former Catholic bishopric in Sabina in the Central Italian region Lazio (Latium). Administratively Poggio Mirteto is in the province of Rieti (formerly part of the province of Perugia) and geographically this municipality is about 45 kilometres (28mi) northeast of Rome and about 20 kilometres (12mi) southwest of Rieti.