Dense small particles on the buttocks are considered to be due to keratosis pilaris, heat rash, folliculitis and other factors, and can be relieved by giving temporary observation, medication intervention and home care. 1. Keratosis pilaris: this is a chronic follicular keratosis skin disease, considered and genetic and endocrine factors, most patients do not need treatment, can be temporarily observed. 2. Heat rash: also known as prickly heat, especially in the hot summer, the patient may be due to local skin impermeability, thus the phenomenon of prickly heat, usually pay attention to keep the buttock skin clean and dry, itching can be relieved by topical glycerine lotion, pus prickly heat can be used as a topical 2% ichthyolite glycerine lotion, Huanglian pumpernickel. 3. Folliculitis: If the patient does not pay attention to the buttock skin clean, it is easy to be infected by external pathogens, thus causing folliculitis disease, there are dense small particles, accompanied by itching and pain symptoms, can be treated with fusidic acid, mupirocin ointment, to alleviate the symptoms. There are other causes for the dense small particles on the buttocks (such as papular urticaria), and it is necessary to cooperate with the doctor to improve the examination and determine the cause before treatment and therapy.