The invention discloses a preparing method of a tobacco flavor enhancer. Tobacco raw materials are subjected to extraction through water and concentration to obtain a tobacco concentrated solution; an ethanol solution is added into the concentrated solution, stirring and standing are conducted, and supernate is extracted and concentrated to obtain the tobacco flavor enhancer; the tobacco flavor enhancer is diluted and then added into reconstituted tobacco or cigarette cut tobacco. The tobacco favor enhancer prepared through the method can improve the quality of the reconstituted tobacco or cigarette cut tobacco and enhance the aroma of smoke, is harmonious and pure in scent, reduces the dry sensation and the offensive odor sensation of smoke, increase the comfort level of cigarettes and can be applied in cigarette production. The preparing method has the advantages that design is reasonable, and the technological process is simple, practical, low in cost and free of pollution; and the preparing method is suitable for industrial production.