From various sources of natural habitat yeasts, which coo 14 transform the constituents of tobacco Powder into flavors, were isolated and three isolates. YOII, M4-1, and M 19-1, were selected These were identified, by their biological characteristics, as Hansenuia ciferri, Pichia acaciae and Candida tropicalis, respectively. Their ferments were extracted with petroleum ether and fractionated into basic, neutral and acidic fractions. The major organoleptic properties of the fermented flavors were detected in the neutral fractions by the sensory test and the yields and threshold values of those fractions were determined and the organoleptic characteristics were described as well.