Objective To comprehend the influences of vitamin C ,KCL and dicynone on blood cross matching of saline and mi-crocolumn gel and to compare them with polybrene crossing matching .Methods Under the conditions with and without the specific antibody ,KCI injection ,dicynone injection ,vitamin C injection and normal saline were added for conducting the immunological reac-tion with corresponding RBC .The influences of 3 kinds of drug on different medium cross matching methods of different mediums . Results The low concentration of vitamin C and KCL does not affect polybrene cross matching ,dicynone makes the experiment to generate pseudoagglutination ;the high concentration of these 3 kinds of drug can cause the test to fail .The sensitivity of the saline medium method is slightly lower ,the influence of vitamin C and KCL on the test is inapparent ,while in the KCL method ,with the dilution of antibody ,the agglutination intensity is weakened and even disappeared .Conclusion 3 kinds of drug all have influences on the mierocolumn gel cross matching method ,especially KCL .