Abstract: Objective To compare the applicability of the combined creatinine-cystatin C equation （CKD-EPIscr-cys） of the Chronic Kidney Disease Epidemiology Collaboration （CKD-EPI） and the Gate’s equation based on the renal dynamic imaging for estimating glomerular filtration rate （GFR） among the elderly patients （age≥80 years old）. Methods The GFR of 99 patients at the age of 80 and over were measured by the two-sample method and as standard. Then,Chronic Kidney Disease Epidemiology Collaboration equation and Gate’s equation were used to determine GFR simultaneously the differences of the two equations in deviation, accuracy, veracity and consistency of GFR prediction. Results Compared with the Gate’s equation, Chronic Kidney Disease Epidemiology Collaboration equation reduce the deviation（P=0.000）, improve the accuracy, 15%, 30% and 50% veracity（P=0.000, 0.000, 0.004） and 95% consistency with statistically significant difference. Conclusions Chronic Kidney Disease Epidemiology Collaboration equation might be a better method to evaluate the GFR of elders without measuring the parameter of morphology and hemodynamics and unilateral renal function.