The cause of red urine can be either physiological or pathological. Physiological causes such as ingestion of red dragon fruit can cause red urine and should be ruled out with care. The most common pathological cause of red urine is suggestive of the development of hematuria. Hematuria is one of the most common symptoms of the urinary system and is divided into visual hematuria and microscopic hematuria. There are many causes of hematuria, such as urinary stones, tumors, inflammation, trauma, glomerulonephritis, and nephrotic syndrome. In the case of finding red urine or physical examination of urine routine suggesting microscopic hematuria, the first step is to identify the cause and treat it symptomatically. Generally speaking, if accompanied by a large amount of meatus hematuria, it is recommended to drink a lot of water in order to prevent the production of blood clots and cause difficulty in urination. Antibiotics can be taken appropriately with cleansing and diuretic drugs to avoid the formation of blood clots and prevent the occurrence of infection. For different etiologies, hematuria caused by urinary stones is often accompanied by pain, while hematuria caused by urinary tumors is usually painless carnal hematuria throughout the whole process, which requires early screening, clear diagnosis and timely surgical treatment. In summary, except for individual foods and fruits that cause infrared urine color, other cases should be alert to the occurrence of blood in urine, and must be promptly hospitalized to do relevant tests to exclude and clarify whether it is hematuria, and timely treatment.