The culture conditions for the production of carrageenase were optimized using one-factor-at-atime method combined with orthogonal array design. With the one-factor-at-a-time method revealed optimal conditions for carrageenase production were 24 h of fermentation period, 28 °C incubation temperature at pH 8.0 with NaNO 3 as nitrogen source and carrageenan as carbon source in MMS media. Further optimization of carrgeenase production by using orthogonal experimental design L 9 (3 4 ) with four factors, temperature, pH, NH 4 NO 3 and carrageenan with their relevant levels revealed optimised conditions for carrageenase production were temperature of 28 °C, pH 8.0, 2 g L -1 NaNO 3 and 2 g L -1 carrageenan. The order of the factors affecting the fermentation process was found to be temperature > pH > NaNO 3 > carrageenan. The temperature played a significant role on the carrageenase production. Higher carrageenase yield with activity of 0.542 ±0.045 U ml -1 was obtained in the optimised medium when compared to those of basal medium. Carrageenase hydrolysed products of carrageenan were identified by LC-ESI-MS as neocarrabiose, neocarrabiose-4 sulfate, neocarratetraose, neocarratetraose-4 sulfate, anhydrogalactose, galactose, galactose-4 sulphate and sulphate.