Kiangan, officially the Municipality of Kiangan is a municipality in the province of Ifugao, Philippines. According to the 2020 census, it has a population of 17,691 people.

It is the oldest town in the province. Kiangan was the former capital of Ifugao until the topology was deemed unfit and moved to neighboring Lagawe.

The Nagacadan Rice Terraces are part of the Rice Terraces of the Philippine Cordilleras World Heritage Site.

The town derives its name from Kiyyangan, an ancient village near the bank of the Ibulao River across the Lagawe valley. The name Kiyyangan is enshrined in Ifugao mythology and is believed to be the dwelling of Wigan and Bugan, the mythological ancestors of the Ifugao.

Kiangan is situated 10.34 kilometres (6.42 mi) from the provincial capital Lagawe, and 355.61 kilometres (220.97 mi) from the country's capital city of Manila.

Kiangan is politically subdivided into 14 barangays.  Each barangay consists of puroks and some have sitios.

In the 2020 census, the population of Kiangan, Ifugao, was 17,691 people, with a density of 88 inhabitants per square kilometre or 230 inhabitants per square mile.

Dialects spoken in Kiangan include Ifugao, Tuwali, Ayangan, Ilocano, Tagalog, and English.