Objectives: To explore the useful thermotolerant ethanologenic yeasts isolated from the Mekong Delta,Vietnam; To characterize and to identify the selected thermotolerant yeasts; To establish the culture collection of newly selected thermotolerant ethanologenic yeasts. A total of 712 yeast isolates was purified from many different kinds of raw material sources in the Mekong Delta, Vietnam; such as ripe fruits, flowers of fruit-tree, cocoa, fermented products, alcoholic fermentation starters, sugarcane, molasses, sawdust, agricultural by-products, soil samples (from fruit gardens, agricultural farms, sugarcane factories) and three-leaf cayratia (Cayratia trifolia L.).  All of these yeast isolates could grow well at 37ºC and there were about 80%, 45% and 10% of yeasts could grow at 40ºC, 43ºC and 45ºC, respectively. More than 80% of yeasts were able to grow in the medium containing 9% (v/v) of ethanol and it was decreased to about 40% and 20% of yeasts growing in the medium supplemented 12% (v/v) and 14% (v/v) of ethanol, respectively.  Because of their thermotolerance and ethanol fermentation capacity at high temperature, 88 yeast strains were selected for characterization and genetic identification.