An extracellular polysaccharide, methylan, was produced under the specific conditions by Methylobacteriurn organophilum from methanol. The specific growth rate of cells was approximately constant regardless of C/N ratio and the specific product yield was maximum at a C/N ratio of 30. Methylan production was suppressed by the deficiency of mineral ions such as Mn** or Fe** ion. The optimal pH for cell growth and methylan production was 7. Whereas the optimal temperature for cell growth was found to be 37°C, that for methylan production was 30°C. The methanol concentration above 4% completely inhibited the cell growth. The initial methanol concentration for the maximal production of methylan was 0.5% (v/v) and above this concentration, methylan production was markedly inhibited. To overcome the substrate toxicity and inhibition for both cell growth and methylan production, a fed-bach culture of intermittent feeding within 5 g/l methanol was conducted under the optimal culture condition. Methylan production of was stimulated by nitrogen limitation and methylan was accumulated up to 8.7 g/l and cell mass also increased up to 12.4 g/l.