The aim of the studies was a comparison of the „liquid-phase” blocking ELISA (LPBE) and MAC-ELISA tests for the detection and quantification of antibodies to SVDV. The second assay is more specific and sensitive and a positive correlation (r=0.88) with the virus neutralisation test (VNT) was found. The overall relationship of reciprocal titres by the used assays showed that log 1.04 by MAC-ELISA was equivalent to log 2.4 by LPBE and log 1.65 by VNT. Variation in results obtained by triplicate testing of individual animals indicates a higher reproducibility of MAC-ELISA then the LPBE. Using MAC-ELISA we could verify the results of our previous assays performed by LPBE; the percentage of the seropositive animals was less than 0.1%. Taking into consideration the fact that Poland is free from SVD, we suppose that these false positive results are due to the presence in sera of unidentified pig enteroviruses. The MAC-ELISA is useful for the fact the estimation of the immunological status of tested animals.