Urinary creatinine is formed by the metabolism of proteins in the body, which need to be eliminated from the body by the kidneys. Low urinary creatinine may be due to poor kidney function, or it may be related to diet, low muscle content, etc. When the protein intake is too low or the body itself contains too little muscle mass and metabolizes it into creatinine, less urinary creatinine will be excreted, but at this time the patient’s urinary creatinine is only mildly low. It may also be due to kidney disease, creatinine in the blood can not be excreted through the kidneys, urinary creatinine decreased, may be the manifestation of renal insufficiency. There are many other causes of low urinary creatinine, it is recommended that patients consult a regular hospital in a timely manner, under the guidance of the physician to improve the relevant examination, clear diagnosis and treatment.