Neonatal erythema toxicum, also known as neonatal erythema allergicum, neonatal urticaria, is a common, benign erythema of unknown origin that occurs in newborns. It is mentioned in the practical dermatology edited by Liu Furen that the disease can occur in about 50% of newborns. The cause of this disease is unknown, and it is thought that it may be caused by the absorption of certain allergens in the gastrointestinal tract or by a metabolic reaction caused by maternal endocrine hormones entering the newborn through the placenta or breast milk. The rash is self-limiting, and there are no serious complications, generally do not need to be treated, but the rash is heavy, widely distributed, appropriate symptomatic treatment is beneficial, can be given a small amount of topical de-inflammatory pine cream, furnace glycerine lotion or powder, as appropriate, to give oral Benadryl syrup, so that the rash quickly fade, shorten the course of the disease, and help to relieve the parents nervous state of mind. Clinically, it should be distinguished from congenital ichthyosiform erythrodermatitis and congenital syphilis. In the former case, the rash occurs symmetrically all over the body and is most obvious in the elbow fossa, fossa, axilla and vulva, with significant keratinization in the palmoplantar area. In the latter case, the mother is a syphilis patient, and the newborn is mostly malnourished, with rashes on the palmoplantar, perioral, genital, perianal and flexural skin of the limbs, with mucosal damage to the nose, mouth and throat, as well as skeletal and visceral damage, and placental abnormalities in syphilitic infants. In addition, the clinical also common neonatal Candida infection skin lesions, manifested as thrush, tongue, gums, cheek mucosa white film; and manifested perianal and diaper area Candida infection, skin erythema erosion, accompanied by papules, herpes, pustules, the pathogenic bacteria mainly from the maternal vagina.