Ømmervatnet is a lake that lies in the municipality of Vefsn in Nordland county, Norway. The European route E06 highway passes along the eastern coast of the lake. The 5.35-square-kilometre (2.07 sq mi) lake lies about 4 kilometres (2.5 mi) east of the village of Drevjemoen and about 20 kilometres (12 mi) northeast of the town of Mosjøen.

• List of lakes in Norway
• Geography of Norway