Abstract: Caffeoyl-coA O-methyltransferase(CCoAOMT)is a key enzyme in lignin biosynthesis. A gene of CCoAOMT family with the cDNA length of 1 080 bp was cloned by RT-PCR and RACE method from young stems of Neosinocalamus affinis and bioinformatics analyzed. The full-length sequence of the CCoAOMT gene from N. affinis was successfully cloned in this studies. The results showed that the gene contained an open reading frame of 777 bp, which encoded a polypeptide of 258 amino acids, the molecular weight of the predicted protein was 28.861 ku, its theoretical PI was 5.33, the gene’s secondary structure consist of α-helix, β-turn, extended strand and random coil; the proportions were 42.25%,8.91%, 32.95% and 15.89%, respectively. The BLASTp results indicated that N. affinis had the highest identity with Bambusa oldhamii. There is a base deletion at the tenth site, and has five variable sites compared with CCoAOMT of B. oldhamii. One relative conserved disordered domain was found in the CCoAOMT gene from N. affinis, B. oldhamii, Phyllostachys edulis and Zea mays. The expression of NaCCoAOMT1 showed that the gene highly expressed in young leaves, upper and middle parts of shoots and stem. This is the first time that NaCCoAOMT1 was cloned in N. affinis. The sequence of NaCCoAOMT1 has been submitted to GenBank with the accession number JF742462.