Blood creatinine 300μmol/L, if it is chronically elevated, it is considered that the patient’s renal insufficiency may reach the decompensated stage, which is relatively serious; if it is acutely elevated, such as diarrhea, infection, urinary tract obstruction, etc., in most cases, the condition is relatively mild, and it may be restored to normal through active and effective treatment. Blood creatinine 300μmol / L, if it is a chronic elevation, the patient is considered to have impaired renal function and reached the stage of decompensation, at this time, the patient’s blood creatinine generally can not return to normal, may be progressively increased, and ultimately can be developed into uremia, and ultimately the need for renal replacement therapy, which is relatively more serious. Blood creatinine 300μmol / L, if acute renal failure, common causes are: heart failure, diarrhea, infection, drug damage, urinary tract obstruction. Generally, it can return to normal after relieving the cause. So it is relatively not serious. Found that blood creatinine 300μmol / L, should be timely to the regular hospital nephrology consultation, improve the relevant examination, clear causes, targeted treatment, to prevent the aggravation of kidney disease.