5-year-old baby can not hold urine may be physiological factors, cystitis, neurogenic bladder and other factors. 1. Physiological factors: 5-year-old baby excessive play, or by excessive shock, may lead to can not hold urine, eliminate the above triggers, may be able to improve on their own, usually does not cause too much impact. 2. Cystitis: It may be related to poor hygiene, which can lead to infection in the bladder. When the infection is serious, it may lead to inability to hold urine, causing urge incontinence, accompanied by urinary urgency, urinary pain and other symptoms, and can be clearly diagnosed through routine urine and urine culture tests. 3. Neurogenic bladder: may be related to cranial tumor, diabetes and other factors, can damage the central nervous system, causing neurogenic bladder, it will lead to the child can not hold urine, may also have difficulty urinating, urinary retention. In summary, the 5-year-old baby can not hold urine, and there are other manifestations, may be the existence of disease factors, it is recommended to seek medical examination and treatment, to avoid aggravation of the lesion.