Armpit melanin deposition, i.e. underarm melanin deposition, can be medically cosmetized by laser, whitening injection and so on. At the same time, it is necessary to reduce the friction of armpit in daily life and change the dietary habits and so on. 1. Laser: The use of laser whitening, so that the laser penetrates the surface layer of the skin, melanin particles in a very short period of time selective absorption of laser light and photothermal effect occurs, so that the melanin particles disintegrate, to achieve whitening effect. The effect can usually be maintained for 2 to 3 years, generally 3 to 6 times for a course of treatment. 2. Whitening injection: In the form of intravenous drip, some antioxidant ingredients are injected into the human body to improve skin quality, lighten melanin and whiten the skin. Generally it can be maintained for 2 to 3 years. Daily attention should be paid to drink more water, avoid wearing tight clothes, and avoid long-term friction under the armpits. Patients are advised to visit the hospital in time and choose the appropriate treatment method under the guidance of the doctor.