Sixteen COMT1 genes were cloned from B.napus,namely BnCOMT1-1 to BnCOMT1-16,by the sequences acquired from Brassica database and in silico cloning.Genome DNA of these genes included four exons and three introns.Intron I could be classfied into two major groups,Group Ⅰ ( 2 106-2 109 bp) and Group Ⅱ ( 2 943-3 057bp),according to the sequence length respectively.Group Ⅰ mainly existed in B.napus while Group Ⅱ kept greater similarity with B.rape and B.oleracea,speculated that gene loss after duplication was the chief contituent of COMT1 gene evolution,and GroupIcould be seemed as a unique feature for B.napus.