The high-copy-number plasmid pSGL1(7.4 kb) was isolated from Streptomyces geobisporous. Its minimal replicon had been determined and sequenced. With the total DNA of S. geobisporus as template, the DNA fragment involving C1027 apoprotein signal peptide encoding sequence (gpp) was amplified by PCR. After this fragment was inserted into the plasmid pSGLN, a derivative plasmid of pSGL1, one new Streptomyces-E. coli shuttle plasmid was obtained namely as pSGLgpp. Using the new vector, we carried out the expression of hsIL-1RI in streptomyces.