The possible causes of a little hidden pain in the penis are as follows: 1, acute urethritis. Can appear in the urethra pain and radiation to the penis, accompanied by frequent urination, urinary urgency, urinary pain symptoms, need to carry out routine urinalysis or urethroscopy to further confirm the diagnosis. 2, when the presence of urethral bladder stones can also appear in the pain of the penis, this time more accompanied by urethral stinging pain, urinary frequency, urinary urgency, but also can be accompanied by the symptom of naked eye hematuria. Need for urinary system ultrasound or urethroscopy to confirm the diagnosis. 3, when suffering from penile cavernous sclerosis can appear penile pain, when touching with the hand can feel the cavernous sclerosis, need to carry out ultrasound examination of the penis to diagnose the existence of cavernous sclerosis. 4, when the existence of urethral tumors can be hidden pain, accompanied by naked eye hematuria, the need to carry out urethroscopy to further exclude. 5, when the suffering of The circumcision can also appear localized swelling and pain, the appearance of the glans can be seen on the glans red, swollen, erythema, etc., there can be a glans, the penis of the radioactive pain.