The formation of freckles is usually related to heredity, sun exposure and other factors, mainly occurring on both cheeks and nose, with lesions of rice grains or pinpoint size, round, ovoid or irregular shape, usually light brown and dark brown in color, usually appearing symmetrically on the left and right. Freckles are relatively common skin diseases, and heredity is the main factor of development, which is autosomal dominant inheritance, with the phenomenon of family aggregation. Usually, if one of the parents has the disease, the children may suffer from this disease, and if both parents have the disease, the chance of the children suffering from the disease will be relatively higher. Meanwhile, sun exposure is also one of the causes of freckles, if the skin is often exposed to ultraviolet rays, it may lead to freckles; usually people with light skin color, such as Caucasian people, will have higher chances of freckles. Freckles occur in exposed areas, such as the cheeks and nose, and are also more common on the neck, shoulders and back of the hands. The shape of freckles is like the size of a grain of rice or the tip of a needle, and the color is usually light brown or dark brown, appearing symmetrically on the left and right, the number of freckles varies from only a few to hundreds, and they are scattered or densely distributed in groups without fusion with each other. It is suggested that patients with suspected symptoms of freckles should go to regular hospitals for consultation in a timely manner, and after clear diagnosis, choose the suitable treatment plan under the guidance of doctors, meanwhile, patients must do a good job in sunscreen to avoid the skin being exposed to sunlight.