The Nemnyuga (Russian: Немнюга) is a river in Leshukonsky, Pinezhsky, and Mezensky Districts of Arkhangelsk Oblast in Russia.

The river flows west, crosses into Pinezhsky District, and turns north.

At the confluence with its right tributary, the Berezov, the Nemnyuga turns north-west and starts meandering.

The only settlements on the river are Sovpolye and Chizhgora, both at the confluence of the Sova, a right tributary of the Nemnyuga.

Downstream from Chizhgora, there is a ferry crossing on the road connecting Arkhangelsk and Mezen.