Male scrotum long black bumps, may be pigmented nevus, wart lesions, local skin infections, scrotal skin malignant tumors and so on. 1. pigmented nevus: nevus is a benign tumor of the human epidermis, which is not cancerous under normal circumstances, so this black bump can be left untreated. You can continue to observe for a period of time, to avoid local damage caused by infection. 2. Wart lesions: common acromegaly, flat warts, filiform warts, common warts, and so on. Most of them are superfluous organisms protruding from the surface of the body, generally the same color as the normal skin color, if there is poor circulation, there may be black bumps. The actual warts can be removed by laser or liquefied nitrogen freezing. 3. local skin infection: there are hair follicles on the scrotum, there may be local hair follicle infection and lead to the formation of black bumps, can be accompanied by local pain, redness and swelling and other manifestations, you need to go to the hospital for examination, after the diagnosis of the need for topical anti-infective ointment to carry out the treatment. 4. Malignant tumors of the scrotum skin: Bowen’s disease, for example, can appear on the surface of the moss-like changes, accompanied by black bumps, accompanied by pain or accompanied by a long period of vesicles, etc., need to carry out a local pathological biopsy, and if the diagnosis is confirmed, then need to carry out the skin of the expansion of the excision treatment. There are many causes of black bumps on the scrotum, it is recommended to go to the hospital for examination, to clarify the cause of the disease under the guidance of the doctor.