Hostovatnet is a lake on the border of the municipalities of Orkdal and Meldal in Sør-Trøndelag county, Norway. The village of Hoston is located on the northeastern shore of the 3.14-square-kilometre (780-acre) lake.The water leaves the lake primarily through the river Vorma which flows east to Vormstad where it joins the Orkla River. The lake Gangåsvatnet lies about 7 kilometres (4.3 mi) to the north. At the southern tip of Hostovatnet there is a short connection to the lake Ringavatnet.