AbstractA simple and sensitive ELISA of mumps IgM and IgG antibodies was described. This assay served as a useful means of rapid diagnosis of mumps virus infection. Coolection of parired serum specimens before day 2 and during the second week of the disease was recommended. A great increase in mumps ELISA IgG in combination with the presence of significant elevation of mumps ELISA IgM level was one of the best proffs of quite recent mumps virus infection. Infulences of false negative reaations and false positive reactions on mumps ELISA IgM were not great. We concluded that the measurement of ELISA IgM antibody along with that of IgG antibody was useful for rapid serological diagnosis of recent mumps infection.