Induced expression of tobacco pathogenesis-related (PR) 1 protein genes was analyzed. The base sequence comparison of the active three genes (PR1a, PR1b and PR1c genes) indicated that there was a well conserved region in 5’ flanking 180 nucleotides in their promotor sequences. Direct gene transfer into tobacco protoplasts by electroporation with the chimeric gene of PR1a promoter and a reporter gene (B-glucuronidase: GUS), and stable transformation of tobacco with a binary vector mediated Agrobacterium infection with the same chimeric gene suggested that the cis-acting element responding to stress or salicylic acid be present in the 0.3Kb sequence of the 5’ flanking region of PR1a gene.