Abstract: The liquefying,sugar-forming,fermenting and other phases of ethanol fermentation using cassava flour were studied. High temperature resistant α-amylase,glucoamylase and Saccharomyces cerevisiae were applied. The data collected were analyzed and calculated by using Excel.The results showed that (a) pH and time had a significant effect on the rate of cassava flour liquefaction (P0.05),but raw materials/water ratio showed no effect (P0.05); (b) the sugar-forming time had a great effect on the amount of reducing sugars (P0.05); (c) the fermentation process was the best with an addition of 0.5% ammonia sulfate yielding an alcohol content of 10.81% (v/v) after 3 days,which was 4.98 times greater than without any nitrogen addition; and,(d) the alcohol produced from the starch amounted to 51.88% by the fermentation.