Abstract: To improve the aroma quality of reconstituted tobacco, a microorganism strain Y-7 capable of fermenting and producing aroma from reconstituted tobacco concentrate was screened from grape surfaces. The strain was molecularly identified, and the fermentation conditions were optimized. Also, its aroma enhancement effect on reconstituted tobacco was evaluated. Results indicated that the strain Y-7 was Meyerozyma guilliermondii, and the optimal growth conditions were 25°C and pH 7.0. Fermentation of 60% concentrated tobacco extract with this yeast for 24 hours significantly increased the content of various volatile aroma compounds. Specifically, ketones, alcohols, acids, phenols, and other compounds with aroma displayed increases of 26.92%, 101.07%, 349.47%, 33.62%, and 20.35%, respectively. Additionally, eleven novel aroma compounds were generated. Y-7 fermentation of concentrated extract notably enhanced the aroma quality and quantity, sweetness, and after taste of reconstituted tobacco, thereby improving its overall quality. In conclusion, Meyerozyma guilliermondii Y-7 shows promising application prospects for shaping the aroma quality of reconstituted tobacco concentrate.