Abstract: wysR3 is the putative regulatory gene in wuyiencin biosynthetic gene cluster from Streptomyces ahygroscopicus var. wuyiensis CK-15. In order to test if wysR3 is involved in the regulation of transcription of wuyiencin biosynthetic genes, we constructed plasmid pSETC-R and introduced into S. wuyiensis CK-15 by conjugation, which produced the over-expression strain. The growth rate of overexpression strain is significantly slower than that of the wild-type. HPLC analysis indicated that wuyiencin production in wild-type and recombinant strains did not have any difference. The method of DNS was applied to the detection of sugar content for two strain's wuyiencin fermentation broth,and the results showed that the sugar content had no difference between them. These results suggested that, under the conditions used here, the DeoR-family regulator did not have any significant function in sugar metabolism or antibiotic production except morphological development.