In order to develop a natural food preservative, dried salviae miltiorrhizae radix (Salvia miltiorrhiza) was extracted with several solvents, and then antimicrobial activity was investigated. The optimum extracting condition for the antimicrobial sustance from the sample, minimal inhibitory concentration (MIC) of the extracted substance against microorganisms were also examined. Antimicrobial activity of the initial ethanol extract from the sample was the strongest compared to those of other solvent extracts such as n-hexane, acetone, butanol, methanol and water. the optimum extractingcondition for antimicrobial substance from the sample was shaking extraction for 2 hours at room temperature incase that 10 volumes of absolute ethanol was added to crushed Saliva Miltiorrhiza. The ethanol extract had strong growth inhibition activity against Gram-positive Bacteria (MIC, 3.13-50$mu extrm{g}$/ml) such as B. cereus, B, subtilis, L. minocytogenes, S. aureus, Sc. Mutans. Among Grampositive bacteria tested, Bacillus species was the most susceptibile to the extracted substance. The antimicrobial activity of the ethanol extract from the sample was weak to Gram -negative bacteria yeasts, for example MIC for Gram-negative bacteria and yeasts was 0.8mg/ml and 0.4-0.8mg/ml , respectively.