Light-emitting diode (LED) photobiomodulation is a new non-thermal light therapy in the field of skin disease treatment, which can be used to treat various skin diseases, such as inflammatory acne, psoriasis, chloasma and so on. With the increasing research of LED light in the field of skin treatment, the equipment based on LED technology has attracted the attention of consumers and dermatologists because of its safety and effectiveness. This article briefly summarizes the effects of light on physical and mental health and skin health, and reviews the development of LED technology and its application in skin diseases.