A pressure on the prostate will be frequent urination, may be due to prostatitis, prostate hyperplasia and prostate cancer and so on. 1. Prostatitis: Inflammation of the prostate gland due to bacterial, viral and other pathogenic infections can cause local vasodilatation of the prostate gland, resulting in swelling, and under the action of the inflammatory factor, the urethra of the prostate gland will become sensitive, so when the pressure on the prostate gland will produce the desire to urinate, which can be manifested as frequent urination. 2. Prostatic hyperplasia: when prostatic hyperplasia to a certain extent, the enlarged prostate may press the prostate urethra and the bladder bottom, so once the pressure on the prostate will be frequent urination. 3. Prostate cancer: If the prostate gland has a tumor, the tumor’s size increases to a certain extent, it may stimulate the bladder wall to become sensitive, when the pressure on the prostate gland touches the tumor, the urinary sensory receptors on the bladder may produce sensation caused by frequent urination. Patients who have frequent urination when the prostate is pressed should go to the hospital in time to find out the cause and receive treatment from a medical professional.