Tangiwai is a 2,696.66 km2 (1,041.19 sq mi) census area and a small rural community in the Ruapehu District of the Manawatū-Whanganui region of New Zealand's North Island. It is located east of Ohakune and Rangataua and west of Waiouru on State Highway 49. In 2018 37.5% of the area's 1,281 residents worked in agriculture, forestry and fishing and 7.1% in manufacturing.