The long foreskin can be turned over to see ecchymosis and a little pain to consider and allergic dermatitis, glans, psoriasis, penile cancer and so on. 1. Allergic dermatitis: mainly related to contact with allergens, patients mainly manifested as the appearance of rashes, itchy or painful skin sensation, redness and swelling. When men have allergic dermatitis in the penile area, it can be manifested as ecchymosis and a little pain when the foreskin is turned over. 2. Glans: disease and pathogen infection, poor sanitation, mainly to local skin and mucous membrane edema, erythema, vesicles, but also easily accompanied by pain, itching, body weakness and other symptoms. Part of the patients with glans may be manifested as long turned over the foreskin can be seen petechiae and a little pain. 3. Psoriasis: the cause is not clear, may be genetic factors, environmental factors together. Psoriasis can involve the whole body skin, scalp, joints and other parts of the body, which can be manifested as red plaques, itchy or painful skin, dry skin, etc. Therefore, some of the patients will have ecchymosis and a little bit of pain when the foreskin is turned over. 4. Penile cancer: the cause of the disease is still unclear, and it may be related to HPV infection and long prepuce, etc. Typical symptoms of patients are pimples on the head of the turtle. Typical symptoms include pimples on the head of the turtle, tingling or burning pain, difficulty in urination, increased secretion, etc., which may be manifested as ecchymosis and a little pain when the foreskin is turned over. It is recommended that patients with ecchymosis and pain in the foreskin be examined by a doctor in order to clarify the cause of the disease and then follow the doctor’s instructions.