In our study, NAM prevented osteoblast DNA damage and cell death caused by oxidative stress. Therefore, NAM can prevent the acceleration of musculoskeletal aging caused by oxidative stress.In summary, the present study shows that NAM significantly enhances osteoblast differentiation by relieving mitochondrial oxidative stress. NAM increases mitochondrial respiration and the expression of antioxidant enzymes via SIRT3, FOXO3A and PGC1A activation, facilitating osteoblast differentiation both in normal physiological conditions and under oxidative stress. On the basis of this study, NAM could be a therapeutic or prophylactic drug to improve bone health or therapeutic agent for the bone diseases caused by reactive oxygen species (ROS).