A non-competitive enzyme-linked immunosorbent assay (ELISA) for LpB∶E was developed. Microtiter plates were used as solid-phase and coated with affinity purified goat antibodies to human apo-B. After incubating the antigen in standards and samples with coated plates, a horseradish peroxidase-labelled goat antibodies to human apo-E were added to the plates to estimate the apo-E with apo-B (LpB∶E) by comparing with the standard carried out simultaneously. 120 samples of fasting human plasma randomly collected were quantitated for LpB∶E and the results obtained were briefly discussed.