Allmannberget is a mountain in the municipality of Oppdal in Trøndelag county, Norway. The 1,342-metre (4,403 ft) tall mountain sits about 3 kilometres (1.9 mi) southeast of the village of Oppdal, easily seen from the European route E06 highway.

The easiest hiking route is from the east-north-east. Drive on the gravel toll road from the E6 highway partially up the Olmdalen Valley, then walk approximately 2.5 kilometres (1.6 mi) to the summit. There is a communication tower on the top of the mountain.

The first element is allmann which means "common/public property" (literally "for all men"), and the last element is the finite form of berg which means "rocky mountain".