Ilfjellet[2] is a mountain in Rennebu Municipality in Trøndelag county, Norway.

It is located in the northeastern part of the municipality, about 13 kilometres (8.1 mi) north of the municipal center of Berkåk and 10 kilometres (6.2 mi) southeast of Å in neighboring Orkland Municipality.

The last element is the finite form of fjell which means "fell" or "mountain".

The river name is derived from Old Norse íla which means "spring".

This Trøndelag location article is a stub.