A two-step optimization strategy was employed to optimize the surface area of sorbent prepared from coal fly ash, calcium oxide (CaO) and calcium sulfate (CaSO4) for flue gas desulfurization. In the first step, a 3 level full factorial design of experiment was used to develop a regression model equation to correlate the significant experimental sorbent preparation variables to the surface area of the resulting sorbent. The three experimental sorbent preparation variables studied are hydration period (x(1)), ratio of CaO to fly ash (x(2)) and amount of CaSO4 (x(3)). In the subsequent step, response surface methodology was used to identify the experimental sorbent preparation variables that maximize the surface area of the sorbent. Through this two-step optimization strategy, it was found that at a hydration period of 10 hrs and drying temperature of 100 degrees C, optimum surface area of 67.0 m(2)/g could be attained by using 5 grams of CaO, 13.7 grams of fly ash, and 7.4 grams of CaSO4 in the preparation mixture. The prediction was verified with experimental runs.