The kinetics of ethanol fermentation by Saccharomyces cerevisiae was studied in a continuous and closed-circulating fermentation (CCCF) system with a polydimethylsiloxane (PDMS) pervaporation membrane bioreactor. Three sequential 500-h cycles of CCCF experiments were carried out. A glucose volumetric consumption of 3.8gL<SUP>-1</SUP>h<SUP>-1</SUP> and ethanol volumetric productivity of 1.39gL<SUP>-1</SUP>h<SUP>-1</SUP> were obtained in the third cycle, with a specific glucose utilization rate of 0.32h<SUP>-1</SUP> and ethanol yield rate of 0.13h<SUP>-1</SUP>. The prolonged fermentation time and good fermentation performance indicate that the CCCF would be a feasible and promising fermentation process technology.