Loei (Thai: เลย; pronounced [lɤ̄ːj]) is a town (thesaban mueang) in the north-east of Thailand. In 2005, it had a population of 22,677. Loei covers the whole tambon Kut Pong of Mueang Loei district.

Loei is the capital of the Loei Province.

Loei lies in the fertile valley of the Loei River, which runs from south to north through the eastern part of the town. A range of hills lies to the east, including the Phu Bo Bit Park found about 3 kilometres (1.9 mi) from the town center.

Loei has a tropical savanna climate (Köppen climate classification Aw). Winters are quite dry and very warm. Temperatures rise until April, which is hot with the average daily maximum at 35.7 °C (96.3 °F). The monsoon season runs from late April through October, with heavy rain and somewhat cooler temperatures during the day, although nights remain warm.