There is a small lump on the right side of the back of the waist to consider may be sebaceous cysts, lipoma or herpes zoster. 1. Sebaceous cysts: Sebaceous cysts are a benign skin lesion due to the blockage of sebaceous gland ducts in the skin, resulting in the accumulation of sebum and the formation of cysts, and are commonly found in the head, face, and back and buttocks, usually with no self-awareness of symptoms, and can be left unattended, but if the cysts are large, then they need to be removed by surgery in time. 2. Lipoma: Lipoma is formed when the tumor-causing factor in the body is affected by heredity, inflammation and other factors, which is activated and leads to the abnormal proliferation of fat cells, and is usually manifested as a localized lump, which is commonly found in the neck, shoulder, back and other parts of the body, and does not affect the human body in general. 3. Herpes zoster: Herpes zoster is an infectious disease caused by varicella zoster virus, the main symptom is a band-like distribution of erythema covered with dense small blisters, preferably in the lumbosacral region, face and neck and other locations, accompanied by neuralgia. Due to the causes of small bumps on the right side of the waist and back are more reasons, it is recommended to go to the hospital for a relevant examination, after the cause is clear to take targeted interventions, to avoid misunderstanding the condition aggravate the symptoms, resulting in a serious impact.