There is a white powder after urine dry, it is recommended to go to the hospital for relevant urine laboratory tests, possible causes: First, urine contains more inorganic salts, such as sodium chloride, potassium chloride and other components, which can appear white after urination dry, as human sweat, after drying on clothes, contains more sodium chloride will appear white powder. Generally there are no symptoms of urinary tract irritation, and the patient does not have any urinary discomfort. It is recommended to drink more water and urinate more appropriately, mainly in summer, when too much water is lost and insufficient rehydration is easily seen. Second, if the urine sugar is too high patients, after urination can also appear after the urine dry will have white powder, may be related to the urine sugar content increased, by dry after sugar analysis out and other factors. It is recommended that a routine urine examination be performed to find out if there is an elevated level of urine sugar, and it is also recommended that a blood glucose measurement be performed to further rule out the presence of diabetes.