A patch of bumps on the skin of the buttocks may be caused by hives, folliculitis, eczema, common warts and other diseases. 1. Hives: physical stimulation, drugs, food, mental stress, overwork may lead to urticaria-like changes in the skin, resulting in buttocks, red spots, mostly accompanied by significant itching. 2. Folliculitis: prolonged sedentary, unclean skin, infection or body immunity decline, bacterial invasion of hair follicles, causing folliculitis, may lead to localized appearance of a pimple. 3. Eczema: summer weather is hot, long-term sedentary local sweating damp, sweat impregnation, may cause eczema-like changes, resulting in a local pimples. 4. common warts: local skin some small damage, human papilloma virus infection caused by common warts, may lead to the local appearance of a pimple. There may be other reasons for the bumps on the buttocks, and it is recommended that the patient go to the dermatology department of the hospital. The reason for this is the fact that it is not a good idea to have a good time.