The causes of a little hidden pain in the penis are mainly external factors, inflammation, stones, penile cavernous hardness, male genital abnormalities and so on. 1. External factors: such as the pain caused by the external blow, or the pain caused by the discomfort on some sports such as cycling. 2. Inflammation: acute urethritis, prostatitis, seminal vesiculitis and other inflammatory diseases may cause pain and radiation to the penis, accompanied by frequent urination, urinary urgency, painful urination symptoms, usually need to carry out routine urinalysis or prostate fluid examination to confirm the diagnosis. 3. stones: when there are urethral bladder stones can also appear penis a little hidden pain symptoms, this time is accompanied by urethral stinging, urinary frequency, urgency, etc., can also be accompanied by naked eye hematuria. Need through the urinary system ultrasound or urethroscopy to confirm the diagnosis. 4. Penile cavernous sclerosis: when suffering from penile cavernous sclerosis may also appear a little hidden pain in the penis, when touching with the hand can feel the cavernous sclerosis, need to carry out ultrasound examination of the penis to diagnose whether there is penile cavernous sclerosis. 5. Male genital abnormality: male erection bending or penis fracture, as well as testicular torsion and other diseases can also lead to a little hidden pain in the penis. Once the above symptoms appear, please go to the hospital in time, complete the examination to confirm the diagnosis as soon as possible, under the guidance of the doctor for treatment.