We invented and verified the possibilities of clinical use of the ELISA Kit for quantification of human serum anti-HBs antibodies. The kit does not employ any labelled antigen but is based on the principle of neutralization. The kit was tested on the panel of sera of the normal population, blood donors, workers at risk workplaces and persons vaccinated with Heptavax-B vaccine. The sensitivity of the kit is 80 mIU/ml, its capture is only slightly worse (in the convalescents) than the capture of the AUSAB (Abbott, USA). Statistical values and frequency distribution at various levels of anti-HBs antibodies in the followed-up group, have been indicated. The kit can be used very well for the follow-up of patients afflicted with virus hepatitis B, for the observation of workers at risk workplaces, for selection of persons eligible for vaccination and for checking the vaccination. It is suitable for the selection of sera for the preparation of specific globulin against hepatitis B and for standardization of this preparation. It is less suited for the compilation of epidemiological surveys where it is important to detect even as low levels of antibodies as 10-80 mIU/ml.