A quantitative screening method for yeast with high activity was established based on the TTC( Triphenyl- tetrazolium chloride) staining method and 96-well plate. The optimal test conditions were 85%( V /V) dimethyl sulfoxide,0. 4% TTC,pH 8,and testing wave length 486nm. This assay was performed in 96-well microtitre plate.Twenty seven strains were cultured in the 96-well microtitre plate with 0%,10%,and 14%( V /V) ethanol. The TTF in cell was detected by microplate reader. Strains with higher TTF absorption values had higher ethanol producing ability. The research presented a novel rapid,high throughput method to screen yeast with high activity and high ethanol yield. As results,6 strains with high TTF absorption value were obtained. This screening method was also very useful to screen all kinds of microorganism and plant cells.