A painless and itchy lump in the scrotum can be considered lipoma, sebaceous cysts and warts, etc. Further examination is recommended to clarify the cause of the disease. 1. Lipoma: If there is a generalized lipid metabolism abnormality, the local skin is subjected to chronic inflammation stimulation and other conditions may cause the appearance of lipoma, resulting in the appearance of the scrotum subcutaneous painless and itchy swelling. 2. Sebaceous cysts: Because sebaceous glands and hair follicles are widely distributed in the scrotum, sebaceous cysts may be caused by blockage of sebaceous gland sacs and exuberant secretion of sebaceous glands due to lack of attention to cleaning. 3. In addition, if there is unclean sexual behavior and other circumstances, also can not rule out the infection of warts and other sexually transmitted diseases, resulting in the appearance of painless bumps. There may be other reasons for a painless bump on the scrotum, and you need to consult a doctor for timely observation and diagnosis of the condition, and standardized treatment under the guidance of a clinician to avoid delays in the condition.