Always having the urge to urinate but urinating very little may be caused by physiological factors such as drinking too little water, nervousness, or considered to be caused by diseases such as overactive bladder syndrome and cystitis. 1. Physiological factors: if you drink too little water, nervous tension, strenuous exercise, may lead to the patient’s body water is too small, always have the desire to urinate but urinate very little. 2. Overactive Bladder Disorder: The cause of Overactive Bladder Disorder is not yet clear, it may be caused by abnormal nerve transmission, underdevelopment of the nervous system and other factors. Patients will have symptoms such as urinary urgency, frequent urination, etc., which manifests itself as always having the urge to urinate but urinating very little. 3. Cystitis: The causes of cystitis include pathogen infection, medication, poor hygiene habits, and low immunity. Symptoms are frequent urination, painful urination, urinary urgency, lower abdominal pain, etc. Patients will have the condition of always having the urge to urinate but urinating very little. There are many reasons for always having the urge to urinate but urinating very little, and it is recommended that patients go to the hospital in time and undergo relevant examinations so as to clarify the cause of the disease.