The DNA segment of the Streptomyces diastaticus strain No.7 M1033 D-xylose Isomerase gene, from -192 to +581 bp according to the translation start site (tss), was cloned in Streptomyces promoter-probe plasmid pIJ4083 from recombination plasmid pUB1 and its M13 subclone S1 respectively. The protoplasts of S. lividans TK24 were transformed with the recombinant, and then detected the promoter activity by measuring the catethol dioxygenase expression. Results of S1 mapping of total RNA of S. di. M1033 indicatedthat: the transcription initiation site of D-XI gene was 40bp upstream the coding region; there was another gene encoded on the antisense strand upstream D-XI gene, with a 114-nucleotide sequence separating their coding regions. According to its DNA sequence, we believed it was the xylulose kinase gene. Data from quantitive S1 mapping also suggested that transcription of the two genes was induced by D-xylose and repressed by glucose.