In a previous study, a gst gene was isolated from the fission yeast Schizosaccharomyces pombe. This gene was dubbed gst I, and was characterized using the gstI-lacZ fusion plasmid pYSH2000. In this work, four additional fusion plasmids, pYSHSD1, pYSHSD2, pYSHSD3 and pYSHSD4, were constructed, in order to carry (respectively) 770, 551, 358 and 151 bp upstream regions from the translational initiation point. The sequence responsible for induction by aluminum, mercury and hydrogen peroxide was located in the range between -1,088 and -770 bp upstream of the S. pombe gst I gene. The same region was identified to contain the nucleotide sequence responsible for regulation by Pap1, and has one putative Pap1 binding site, TTACGTAT, located in the range between -954 approximately -947 bp upstream of the gst I gene. Negatively acting sequences are located between -1,088 and -151 bp. These findings imply that the Pap1 protein is involved in basal and inducible transcription of the gst I gene in the fission yeast S. pombe.