Children always itch in the buttocks may be eczema, pinworms, diaper dermatitis and other diseases. 1. Eczema: the cause of the disease is currently unknown, is internal and external factors lead to epidermal and dermal superficial inflammatory diseases, may be related to heredity, allergies, infections and so on. Often manifested as perianal erythema, papules, accompanied by itching, etc., can appear in the child’s buttocks always itchy symptoms. 2. Pinworm disease: The disease is an infectious disease caused by pinworm parasites in the human intestinal tract. After infection with pinworms, female adult worms will crawl around the anus and lay eggs, so that the perianal and perineal areas of intense itching, especially at night, can appear in the child’s buttocks always itchy symptoms. 3. Diaper dermatitis: may be the child’s buttocks long-term contact with feces, urine and other excreta, while repeatedly rubbing with the diaper caused by inflammatory diseases. Often manifested as erythema, papules, papules, accompanied by itching, etc., can be manifested as symptoms of always itchy buttocks. It is recommended that children with itchy buttocks should go to regular hospitals in time to get a clear diagnosis and standardized treatment under the guidance of doctors.