Continuously increasing demand for non-petroleum based products and energy is one of urgent issues to be solved in recent years.Microbial production of industrially valuable compounds from plant biomass is of great economic and environmental significance.To suit this demand, microbial cells should be fortified against multiple stresses.We isolated thermotolerant S.cerevisiae exhibiting confluent growth at 41℃.Starting from this strain, we have created superior hybrid strain, T J14, showing resistance against high-temperature and low pH by genetic cross with high ethanol producer but displaying thrmosensitive trait.T J14 produced 45 g/l ethanol by semi-simultaneous saccharification and fermentation (SSSF) of 100 g (w/v)/l cellulose at 39℃ which is a significantly higher concentration than reported at high temperature.