Algae organisms are rich sources of biologically active metabolites which can be used in pharmaceutical industry. The purpose of this study was to evaluate Chlorella vulgaris acetone and ethanolic extracts for antimicrobial effects against Bacillus subtilis. The algae extract was investigated for in vitro antimicrobial activity against Bacillus subtilis PTCC1156 using disk diffusion and dilution method. It was found that the Chlorella vulgaris has good inhibitory effect on Bacillus subtilis. Inhibitory effects of each extract varied considerably among the microorganisms. Maximum antibacterial activity was observed in acetone extracts. Its MIC against Bacillus subtilis WAS determined 3 mg/mL.