The darkening of the color of the private parts may be a natural physiological phenomenon in the process of growth and development, or it may be related to friction stimulation, long-term chronic inflammation and other factors, which can be relieved by relieving local friction and medication. 1. Physiological phenomenon: the darkening of the color of the private parts is related to the secretion of hormone levels, with the growth of age, the hormone level secretion is perfect, stimulate the vulvar skin melanin deposition, which is a normal physiological process of women, do not need treatment. 2. Friction: the black color of the private parts is related to the local friction and stimulation of sex life, and wearing over tight underwear or pants, etc. It is recommended to wear loose and breathable clothes. It is recommended to wear loose and breathable cotton underwear, and keep the vulva clean and dry. 3. Disease factors: If long-term vulvovaginitis produces vulvar itching, repeated scratching and stimulation with hands, resulting in local skin blackening, the need to actively treat the inflammation, the inflammation will gradually return to normal after control. If the bacterial cause of vulvovaginitis, you can use metronidazole effervescent tablets for vaginal medication, external rubbing erythromycin ointment relief. The black color of the private parts in the exclusion of physiological factors, need to actively go to the hospital for treatment. The above drugs need to be used under the guidance of a doctor.