A cDNA encoding banana lectin (BanLec) was obtained by using RT-PCR from banana fruit and sequenced. Comparison of this cDNA sequence with the sequence of BanLec gene registered in GenBank (Accession No. AF001527) showed that both sequences shared high similarity with only nine nucleotieds and four amino acids difference. RT-PCR analysis of the expression patterns of BanLec gene in different tissues and different fruit ripening stages of banana suggested that this cDNA not only expressed specifically in fruit but also expressed developmentally during fruit ripening. Relative quantification of expression level of BanLec gene in different tissues and different ripening stages were carried out by using computer software.