The causes of age spots are mainly related to aging, but may also be related to heredity, sun exposure, and environmental factors. 1. Ageing. With age, the physiological function of skin will gradually decline, so it is easy to form some seborrheic keratinization, commonly known as age spots. 2. Hereditary factors. Age spots have certain hereditary tendency, for people with similar hereditary history in the family, the time of age spots will be advanced and the chances of age spots will be increased obviously. 3. Sun exposure. Prolonged exposure to the sun and ultraviolet rays will cause different degrees of damage to the skin, and when the physiological function of the skin is affected, it is easy to appear age spots prematurely. 4. Environmental factors. The environment contains irritating chemicals, and repeated contact with the skin may induce the appearance of pigmentation. Due to the different physique of individuals, the causes of age spots may also be different to a certain extent, and the specific conditions can be analyzed after consultation with a specialist.