The skin is always exposed to the environment, because it is localized at the outermost layer of the body. Therefore, it is well recognized that the skin is continuously affected by changes in environmental factors and responds to those in order to maintain homeostasis. The accumulation of those responses is considered to be a factor that accelerates skin aging, which is supported by differences of perceived age between twins who have spent their lives in different environments. Thus, the concept of the exposome, which is the sum of all factors the body is exposed to from conception to death, has been proposed to discuss the influence of environmental factors on skin aging. The author introduces the contribution of the exposome to skin aging focusing on sunlight, air pollutants and humidity. Those environmental factors increase oxidation levels in keratinocytes and fibroblasts, which results in the onset of the aging process. These results support the importance of daily care on moisturizing and anti-oxidation in order to delay skin aging.