Rubella virus antibodies were measured in 85 sera from pregnant women by using a new latex test, and the results were compared with those obtained by using hemagglutination inhibition. The sensitivity of the latex test was 98.4%, specificity was 66.6% and the predictive value of a positive result was 90%. The latex test is a simple test and has much shorter reaction time than that of the hemagglutination inhibition.