A new actinomycete strain designated as Streptomyces sp. SZS39 was isolated along with other 61 bacterial strains from a soil in Japan using ISP2 agar medium.As a result of antimicrobial screening, the acetone extract of the strain SZS39 exhibited promising antimicrobial activities against Bacillus subtilis, Saccharomyces cerevisiae, and Schizo saccharomyces pombe. Isolation and identification of the antimicrobial principles from the strain SZS39 was accomplished. As a result of analysis using NMR and MS spectra, the main antimicrobial compound was identified as actinomycin X2. To identify the strain SZS39, a partial 16S rRNA gene sequence from the strain SZS39 was determined and found to have high identity (99%) with known actinomycin producer Streptomyces padanus MITKK-103.