Abstract: Total RNA was extracted from liver cells of landrace, pMBL-A gene was amplified by RT-PCR. It was cloned to pMD18-T vector, then the mannan-binding lectin A gene of landrace was obtained. It was subcloned to pPROEXHTb vector for expression, recombinant expression plasmid was constructed. The recombinant expression plasmid was transformed into E.coli and was induced to express recombinant protein of pMBL-A. The expressed protein was identified by SDS-PAGE. The cDNA of pMBL-A gene was successfully cloned, its full-length was 875bp including the whole ORF. Recombination protein was pronuleus expressed, it provides affordance for the research of genetic character of the gene and genetic breeding of pigs.