There has been no timetable announced for the proposed plant, which would be similar to a research reactor in Tehran that produces medical isotopes. Iran's lone energy-producing reactor is in the Persian Gulf port of Bushehr.
Iran also is working on a so-called "heavy water" reactor that doesn't require enriched uranium fuel.
The US and other do not specifically object to Iranian reactors, but fear Tehran's ability to make nuclear fuel could lead to atomic weapons. Iran denies the charges.
Today's report says the new site is near Zarghan, about 670 kilometers (420 miles) south of Tehran. It said the plant aims to produce medical and agricultural radioisotopes.