The long bumps under the skin of pubic hair may be caused by folliculitis, epidermal cysts and other diseases. 1. Folliculitis: folliculitis is mainly caused by Staphylococcus aureus and other pathogens infecting the hair follicles, sweating, low immunity and other factors may also trigger the disease, which occurs in the head, face, pubic area, etc. The patient’s epidermis may appear red pimples, accompanied by itching, tenderness symptoms. 2. Epidermoid cysts: benign skin tumors and the most common skin cysts. It can be secondary to trauma, surgery, etc., leading to the appearance of cysts containing keratin in the dermis, manifested as a palpable swelling under the skin, usually hard texture, clear boundaries. If there is a case of pimples under the skin of pubic hair, it is recommended to go to a regular hospital for examination and to clarify the cause of the disease.