Kidney function test includes blood creatinine, urea nitrogen and other items. The precautions for patients before kidney function test are: keep fasting, eat light diet, avoid taking drugs that affect kidney function, avoid strenuous exercise and so on. 1. The best fasting test: renal function test needs to draw blood, in order to ensure the accuracy of the test, the patient’s renal function test needs to keep fasting. 2. Light diet: two days before the test, patients should maintain a light diet, avoid eating too greasy and high protein diet, so as not to affect the test results. 3. Avoid taking drugs that affect renal function: before the test, patients should also pay attention to avoid taking drugs that affect renal function, if they can’t avoid it, they should reduce the dosage under the doctor’s advice, so as not to affect the test results. 4. Don’t exercise strenuously: Strenuous exercise may cause creatinine increase and affect the result. It is recommended that patients should go to regular hospitals for renal function tests, and standardize the treatment in time when abnormalities occur.