Abstract: Mitochondria are semi-autonomous organelles where the chemical energy required for all cellular activities including biosynthesis, respiration, secretion, and mechanical movement in living organisms which is supplied by mitochondria. Mitochondriaassociated endoplasmic reticulum membranes (MAMs) are lipid raft-like domains closely associated with mitochondria and located between mitochondria and endoplasmic reticulum (ER). MAMs not only structurally connect ER and mitochondria but also are enriched in a variety of linking and functional proteins, so MAMs must have an impact on ER and mitochondrial function. This review focuses on the structure and molecular composition of MAMs, and the effects of MAMs on mitochondrial function. The main focus was on mitochondrial fusion, mitochondrial fission, mitophagy, mitochondrial energy metabolism and mitochondrial reactive oxygen species production. It is hoped to provide a reference for researchers who can improve related diseases by regulating mitochondrial function through MAMs.