Objective To establish an ELISA method for the detection of mumps virus titer and verify it, so as to shorten the detection time and provide technical support for emergency inspection.Methods Vero cells were infected with reference standard of mumps vaccine virus. With mouse ascites as the primary antibody and HRP-labeled goat anti-mouse IgG as the secondary antibody, the inoculation concentration of Vero cells, centrifugation time after virus inoculation, virus infection time, antibody concentration, sealing fluid type, and fixation method and time were optimized to establish an ELISA method for detecting mumps virus titer. The specificity, accuracy, precision and linearity were verified, and the results were compared with those of micro-cytopathic method.Results The established ELISA method was as follows: adding Vero cell suspension with concentration of 3 × 10~5 cells/mL to 96-well cell culture plate for 24 h; adding samples and reference standard, centrifuging at 236 × g for 2 h, and then culturing for 48 h; fixing the cells with 4% paraformaldehyde for 10 min, then treating with PBS-0. 5% TritonX-100 for 30 min; after sealing with 5% skim milk powder, adding primary antibody(1∶1 000 diluted) and secondary antibody(1∶2 000 diluted); using TMB for color development and sulfuric acid to terminate the reaction, and detecting the A_(450) value. The established method had good specificity for mumps virus. The relative bias(RB) in detecting virus titer of different concentrations of reference standard was less than 10%. The coefficient of variation(CV) of virus titer of reference standard detected six times in different working days was 3. 9%. The linear slope of the method was 0. 920 6 and the correlation coefficient(r) was 0. 993 9. There was no significant difference in virus titer results detected by the two methods(t = 2. 049, P > 0. 05).Conclusion The established ELISA method for detecting mumps virus titer has strong specificity, good accuracy and precision, and has good consistency with the detection results of micro-cytopathic method, which can obviously shorten the detection time