Purpose: Ethyl carbamate(EC) is a natural carcinogen produced during the fermentation and storage of fermented foods. Previous studies have shown that the BTN2 gene of Saccharomyces cerevisiae is related to EC metabolism and that different fermentation systems may influence the transcription of BTN2， which in turn regulates EC. Method: A BTN2 knockout strain was used to replace the traditional Chinese koji and a strain of Pentococcus pentosaceus， isolated from Chinese koji， was introduced into the fermentation of Huangjiu. We aimed to investigate the regulatory mechanisms of BTN2-modified yeast on EC and the effect of different storage conditions on the physicochemical quality of Huangjiu under different fermentation systems. Results: Fermentation with BTN2 knockout strain effectively reduced EC production， lowering EC content to 58.8% compared to the control. The inhibitory effect was more pronounced in mixed fermented with P. pentosaceus， where EC content decreased to 13.2% of the control level. Additionally， storing at 4 ℃， shortening the storage period and avoiding light were found to be effective strategies for reducing EC. Conclusion: Mixed fermentation contributed to the improvement of overall Huangjiu quality， while storage at 4 ℃ under light exclusion helped stabilize the accumulation of free amino acids and esters， as well as maintain the color， leading to better sensory qualities. This study provides a theoretical basis for reducing ethyl carbamate in Huangjiu and offers new insights into mitigating EC accumulation during storage.