Abstract:XY355 promoter, a petal-specific promoter, was amplified from the genome of rapes (Brassica napus) by PCR. Then the XY355 promoter was connected with a maize anthocyanin regulatory gene Lc to construct an expression vector pXY60.The vector was introduced to the Agrobacterium tumefaciens strain LBA4404 by freeze-thaw method .The explants of leaf discs from tobaccos (Nicotiana tabaccum L.) and petunias (Petunia hybrida) were transformed by LBA4404 respectively. The results of the PCR analysis among these regenerated plants indicated that Lc gene was integrated into the genomes of transgenic tobaccos and petunias respectively. The observation of the phenotypes showed the flower color of transgenic tobaccos was changed from light red to red and that of transgenic petunias was changed from white to light purple.