To optimize the soy paste production,proper starter cultures and strains were selected and separated by 16S rDNA.Several soy pastes were made using one or mixed separated strains,and their storage stabilities were measured with antagonistic effect of E.coli and B.cereus.Experimental designs were applied to optimize the mixture ratio of the selected cultures for soy paste.Fifteen candidate points were examined for their significance on soy paste using the modified distance design.