Beta-xylosidase gene from Streptomyces sp. CH7 was cloned by using Escherichia coli DH5alpha as a host and pUC18 as a cloning vector. Two clones, namely, N1 and N2 capable of expressing beta-xylosidase gene showing beta-xylosidase activity of about 30 folds higher than that of E.coli DH5alpha/pUC18 were obtained. The recombinant plasmids from both clones namely pCH7-1 and pCH7-2 had similar size of 6.3 kb. Both plasmids showed similar restriction patterns by SmaI indicating they had the same DNA insert of 3.6 kb in size. The restriction analysis of the DNA insert showed that it contained four SmaI sites and after restriction cut with this enzyme giving one fragment each of 1.8 and 0.6 kb and three fragments of 0.4 kb. When the DNA insert was subcloned in pUC19 calling pCH7-1(19), E.coli DH5alpha receiving this recombinant plasmid was still able to show beta-xylosidase activity although only about 10 folds higher than that of E.coli DH5alpha/pUC19. The result indicated that the cloned gene also carried its own promoter and was able to be expressed under it in E.coli although with lower efficiency than that under Plac on the cloning vector.