The province of Terni (Italian: provincia di Terni) is the smaller of the two provinces in the region of Umbria in Italy, comprising one-third of both the area and population of the region. Its capital is the city of Terni. The province came into being in 1927, when it was carved out of the original unitary province of Umbria.
It has an area of 2,127.18 km and a population of 215,423 as of 2025. The only towns with a population over 10,000 are Terni, Orvieto, Narni and Amelia.