Optimized fermentation medium and cultural conditions for the production or exopolysaccharide KS-1 with Bacillus polymyxa KS-1 was following as; 30g g1ucose, 2.59g yeast extract, $2.5g KH_2PO_4, 0.5g NaCl, 0.3g MgSO_4.7H_20, 0.1g CaC0_3 0.05g, FeSO_4.7H_2O, and 0.05g MnS0_4 . 4H_20in 1 liter distilled water. The exopolysaccharide production was influenced by the by the temperature and pH, the optimal conditions for the production of exopolysaccharide KS-1 seemed to be $30^{circ}C$ and pH 7.0, respectively. About $10.3g/ell$ of maximum exopolysaccharide was obtained al the initial pH 7.0, $30^{circ}C$, 2vvm of aeration rate and 400 rpm of impeller speed in a jar fermentor.