Hidden pain on one side of the perineum in men may be caused by chronic prostatitis, prostate abscess, urinary tract infection and other reasons. 1. Chronic prostatitis: If you have chronic prostatitis, the pathogenic bacteria will stimulate the urethral mucosa of the prostate, causing redness, swelling and erosion of the mucosa, and the prostate glands will become inflamed and enlarged. If the inflammation spreads locally, it may cause pain on the perineum side. 2. Prostate abscess: Patients with prostate abscess may have bladder irritation signs, such as frequent urination, urgency, painful urination and pain in the perineal area. If in the pre-abscess stage or if the symptoms are mild, men may experience vague pain on the perineum side. 3. Urinary tract infection: If there is a urinary tract infection, usually manifested as burning sensation in the urethra, frequent urination, urgency, painful urination, discomfort in the suprapubic bladder area, discomfort in the perineum, etc., the patient may experience pain on one side of the perineum. There may be other causes of perineal pain, so it is recommended that the patient go to the hospital in time to clarify the cause of the disease and take corresponding treatment measures.