Ichthyosis is due to congenital abnormalities in the stratum corneum that make it difficult to store water. Congenital defects in lipid-like metabolism can also be associated with scale formation. Dominant ichthyosis vulgaris is inherited by autosomal dominant inheritance, but each generation of patients may not always have an obvious and easily visible rash. Sexually linked ichthyosis is inherited by an X-chromosome recessive gene and generally occurs only in males. The STS gene structure has been shown to be completely absent in 90% of patients, with the remaining 10% exhibiting partial deletions and point mutations. If the disease occurs in women who are pure gametes, the symptoms are not obvious and only dry skin and some scaling of the legs are present. There is no cure for ichthyosis. The patient’s skin is dry, especially in the cold season when sebum secretion decreases, and the rash is obviously aggravated. Therefore, bathing should not be too diligent, and strong alkaline soap should not be used more often, so that sebum is less prone to chapping. Severe patients can take aromatic retinoic acid 25-35 mg every other day, but there are certain side effects. 10% urea cream, 0.05-0.1% vitamin A acid ointment, 40-60% propylene glycol solution containing 6% salicylic acid and glycerin gel ointment can not eliminate the scales, but can make the patient feel comfortable.