HML (Hypsizigus marmoreus lectin) was isolated from the mushroom Hypsizigus marmoreus using CM cation exchange, bovine submaxillary gland mucin affinity column and TSK-GEL G3000SW gel filtration chromatography. The results of SDS-PAGE, MALDI-TOF MS and gel filtration analysis of HML indicated that the lectin was a dimer with each subunit of 9.5 kDa. The partial amino acid sequences of HML were determined by N-terminal sequencing of peptides obtained by trypsin or Glu-C endopeptidase digest of the lectin. In the hemagglutination inhibition assay, HML did not bind to any mono- or oligo-saccharides tested. Among the glycoproteins examined, asialo-fetuin was the strongest inhibitor.