Abstract: Objective In order to evaluate the difference between plaque reduction neutralization test(PRNT)and reverse passive hemagglutination inhibition(RPHI)test on human anti-Japanese encephilitis antibodies.Methods Pre-and postimmunization sera collected from 450 children aged 6-10 years old after vaccination with inactivated JE were detected by both methods.Results No significant difference was found between these two methods when they were used to measure the postimmunization sera,but significant differnce was found between these two methods when they were used to measure the preimmunization sera.Conclusion PRNT was more sensitive than RPHI when they were used to measure the anti-Japanese Encephilitis antibodies.