The Islamic Republic of Iran Railways (abbreviated as IRIR, or sometimes as RAI, or as IRI Railway) (Persian: راه‌آهن جمهوری اسلامی ایران, romanized: Râh âhan-e Jomhuri-ye Eslâmi-ye Irân) is the national state-owned railway system of Iran.

The Ministry of Roads & Urban Development is the state agency that oversees the IRIR.

[3] Almost all of this is standard gauge of 1,435 mm (4 ft 8+1⁄2 in), but 94 km are Russian gauge of 1,520 mm (4 ft 11+27⁄32 in) to link up to ex-Soviet Union border states.

There is also the no-longer-isolated Indian gauge section of 1,676 mm (5 ft 6 in) from Zahedan to the Pakistan border that continues to Quetta and the Indian sub-continent.

In 2006, IR reported that it possessed 565 engines, 1,192 passenger coaches, and 16,330 wagons.