0.05).Every one of the patients completed hemodialysis except one needing to rebuild blood circulation by changing another dialyzer, whose vein pressure became higher and the dislyzer was of cruor as it was difficult to build blood circulation. The rate of success has reached 99 percent. Conclusion There is no influence upon the general cruor mechanism when using hemophan dialyzers to heparin-free hemodialysis treat the acute or chronic renal failure. This simple method is not only effective but also safe, which can provide a reliable measure to rescue patients suffering from acute or chronic renal failure with serious tendency of hemorrhage.