The cultural condition of Enterobacter agglomerans U-1, a polysaccharide producing soil bacterium, was examined. The optimal medium composition was that contains the following components per liter of distilled water; sucrose (23.75 g/L), peptone(2.06 g/L), yeast extract (0.5 g/L), KH₂PO₄(1.0 g/L) and MgSO₄-7H₂O(1.0 g/L). The optimum temperature for polysaccharide production was 30℃, where 8.5 g/L of polysaccharide was produced. The apparent viscosity of fermentation broth after 3 days was 240 mPa.s. at 70sec^(-1). The product yield and specific productivity were 36% and 142.07 ㎎/g/h.