The reasons for more urine after drinking water are as follows: First, after drinking a lot of water, after absorption in the gastrointestinal tract, water enters the body’s circulation, causing an increase in circulating blood volume, which is then filtered by the kidneys, and after feeling the increased pressure, there will be a performance of enhanced filtration, which will discharge excess water out of the body to complete the function of the kidneys to regulate the water-electrolyte balance. Secondly, after drinking a large amount of water, the anti-diuretic hormone secreted by the body will be reduced, and diuresis will occur, and the urine volume will increase to maintain the water-electrolyte balance. Third, if the drinking water contains more sugar or contains certain ingredients such as caffeine, it can lead to the effect of osmotic diuresis, which can lead to increased urination. Fourth, the human body fluids themselves in a slightly satiated state, then the appropriate amount of drinking water can increase the filtration of the kidneys and lead to an increase in the discharge of body fluids, increased urine production, there will be increased urination phenomenon.