The pH value of urine is between 4.5 and 8. It is a dynamic process that changes according to the amount of water consumed, the structure of the diet, the medication taken or the metabolic environment in the body, etc. As long as it is between 4.5 and 8, it is normal. It is also related to the patient’s lifestyle and diet structure. Patients with long-term vegetarian diet will have a relatively high pH, while patients with long-term meat diet will have a low pH. Patients with lung disease will also have a series of changes in pH, because human respiration exhales oxygen and expels carbon dioxide, and carbon dioxide combines with blood in human body to form carbonic acid, which has the effect of regulating pH in human body. Also, taking diuretic drugs or anti-infective drugs may disturb the internal environment of the human body and cause abnormal pH, but if the pH of urine is between 4.5 and 8, it is normal and can be observed dynamically and is not a state of disease.