Leucoderma and vitiligo differ in causes, symptoms, and treatments. 1. Etiology: The cause of pityriasis alba is unknown. The causes of vitiligo include polygenic inheritance, autoimmune response, neuropsychiatric factors, melanocyte self-destruction theory, free radical defense function defective theory and so on. 2. Symptoms: (1) white furfura: manifested as pale white spots, the surface of a small number of fine bran-like scales, often accompanied by dry skin. (2) vitiligo: lesions for pigmentation loss spots, often milky white, smooth surface without rash. The white spot boundary is clear, the surrounding normal skin tends to deepen pigmentation, the white spot within the hair is normal or whitened, the condition of the progress of the white spot to expand. A few patients have localized itching before the onset of the disease. 3.Treatment: (1) white chaff rash: it can disappear naturally and generally does not need treatment. Oral vitamin B complex, 1% hydrocortisone cream, fluorine easy ointment. Avoid excessive cleaning of the affected area with alkaline soap, etc., and use moisturizing cream. (2) vitiligo: reduce sun exposure, friction trauma. Topical glucocorticoids (mometasone furoate, hydrocortisone butyrate) or calcium-modulated neural phosphatase inhibitors (such as tacrolimus ointment, pimecrolimus ointment) can be used. Phototherapy (e.g., excimer laser) and masking therapy are also available. Patients with pityriasis alba or vitiligo should go to the hospital in time for standardized treatment under the guidance of a doctor. Drugs need to be used in accordance with medical advice.