If the urine color is abnormal, it is necessary to decide whether it is a disease state based on the specific urine color and the patient’s symptoms. First, if the urine is dark yellow in color, the presence of concentrated urine or jaundice should be considered, and further urine specific gravity tests, urine bilirubin tests, and liver function tests should be performed to determine this. Secondly, if the urine is red in color, it is necessary to consider whether there are infectious diseases, or stones or tumors, etc., and routine urine examination is required. If there is an increase in red blood cells in the routine urine examination, further ultrasound or CT examination of the urinary system is needed to exclude related diseases. Third, if the urine is green in color, it may be due to a large number of antibiotics, or vitamin B, or a Pseudomonas aeruginosa infection. In this case, you need to carry out a urine culture test and stop taking the relevant drugs before observing the change in urine color. Fourth, if the urine is soy sauce-colored, consider whether there is an acute hemolytic reaction. If it appears during a blood transfusion, it should be considered as an acute hemolytic reaction due to blood group incompatibility. If it appears after eating fava beans, consider whether it is fava bean disease, caused by the lack of glucose dehydrogenase 6-phosphate in the body.