The complete amino acid sequence of Agrocybe cylindracea lectin was determined from the peptides obtained by chemical cleavages and enzymatic hydrolyses. The sequence shows 19.1% and 36.8% identity with those of human galectin-1 and Coprinus lectin-1, a fungal galectin, respectively. Seven residues, which are commonly found in carbohydrate recognizing domain (CRD) of galectins, were conserved. However, several insertions in the sequence, compared with those of human galectin-1 and Coprinus lectin-1, suggest that beta-strands S2, F3, and S4 and the loop structures between beta-strands F2 & S3 and F5 & S2 are different from those of galectins reported so far.