The Mekhrenga is a river in Plesetsky and Kholmogorsky Districts and in the town of Mirny of Arkhangelsk Oblast in Russia. It is a left tributary of the Yemtsa River. It is long, and the area of its basin . The principal tributaries of the Mekhrenga are the Shorda (left), the Myagdoma (right), and the Puksa (left).