A 13-year-old girl’s frequent urination should be identified as physiologic or pathologic. Physiologic causes include drinking too much water or consuming drinks with too much sugar, cold weather, etc., which can lead to frequent urination. In addition, there is a disease called psychogenic urinary frequency syndrome, often due to mental stress, emotional tension or parents do not pay enough attention to the child, resulting in frequent urination, which is the physiological causes of frequent urination. Pathological urinary frequency has more causes, the most common is the urinary system infection, the child will often have urinary urgency, urinary pain and other symptoms, you can check the urine routine and urine culture to assist in the diagnosis. Urinary stones, inflammation of the vulva, occult spina bifida, and neurogenic bladder can also cause frequent urination. There are also endocrine disorders such as diabetes mellitus and uremia that can cause urinary frequency. In addition to frequent urination, there will be symptoms such as increased urine output, thirst and wasting. Urine routine, urine specific gravity, ultrasound of the urinary system, and even water fasting test and blood sugar should be actively improved to clarify the diagnosis.