The present invention relates to a composition for promoting mitochondrial biogenesis, which includes azelaic acid as an active ingredient. It was confirmed that azelaic acid is a compound mainly contained in cereals and natural products and has the advantage of no or little side effects, and mitochondrial autophagy and mitochondrial DNA synthesis in cells are induced, thereby ultimately having activity of increasing mitochondrial density. Therefore, azelaic acid can be used for the treatment of mitochondrial dysfunction-associated disease by the failure of homeostasis control of the mitochondria, for example, mitochondrial activity or the decrease in the number of mitochondria. In addition, azelaic acid can be provided to reinforce a muscle function and prevent muscle aging using the activity, and to be effectively used in food material, a pharmaceutical composition, and health functional foods for treating mitochondrial dysfunction-associated disease, reinforcing a muscle function, or preventing muscle aging.
