Normally, the normal range of urinary creatinine is 7 to 18 mmol/24h in adult males; 5.3 to 16.0 mmol/24h in adult females. Urinary creatinine is formed by blood creatinine through glomerular filtration, so the level of urinary creatinine is affected by blood creatinine. If abnormal urinary creatinine is found, it should be combined with blood creatinine and other related indicators of renal function to comprehensively determine the renal function. High urinary creatinine can be seen in physiological factors such as starvation and strenuous exercise, pathological factors such as diabetes mellitus, hypothyroidism, etc. Low urinary creatinine can be seen in renal failure, progressive muscular dystrophy, hyperthyroidism and other diseases. If the patient found abnormal urinary creatinine, it is recommended to go to the regular hospital in time, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.