Painful blisters in the buttock groove may be related to herpes simplex, perianal eczema, jock itch and other causes. 1. Herpes simplex: usually caused by herpes simplex virus infection, which can be induced by cold, excessive fatigue, mental stress and low immunity. In the early stage of herpes simplex, it will be accompanied by burning sensation on the skin, followed by small blisters and pain. 2. Perianal eczema: it may be related to the stimulation of secretions caused by anal and intestinal diseases, or it may be induced by wearing tight and breathable underwear. It can cause erythema, papules and small localized blisters in the buttock cleft area. 3. Ringworm: mainly related to dermatophyte infection, may be related to localized sweating or wearing airtight clothes. Ringworm can cause erythema and papules to appear on the groin skin, and can also spread to the buttock cleft skin, with blisters, itching and tingling symptoms. When blisters appear in the gluteal cleft area. It is recommended to consult a doctor in time, follow the doctor’s instructions for further examination, clarify the cause with the help of the doctor, and carry out targeted treatment or therapy.