The Iza is a left tributary of the river Tisa in northern Romania. Its source is in the Rodna Mountains. It flows into the Tisa near the city Sighetu Marmației. It passes through the communes Săcel, Săliștea de Sus, Dragomirești, Bogdan Vodă, Șieu, Rozavlea, Strâmtura, Bârsana, Oncești, Vadu Izei, and Sighetu Marmației. Its drainage basin covers an area of 1,293 km2 (499 sq mi).:23 Its length is 80 km (50 mi).
The following rivers are tributaries to the river Iza: