［Objective ］ To investigate the types and content differences of volatile flavor compounds in Daqu,used for the production of Fuyu flavor Baijiu,from different production months.［Methods ］ Headspace solid -phase microextraction -gas chromatography -mass spectrometry (HS-SPME -GC-MS) was used to analyze the volatile aroma components of Daqu used for brewing Fuyu flavor baijiu,which were released in seven different months.［Results］ A total of 97 volatile aroma compounds were detected in Daqu,including 4 alcohols,6 esters,9 aromatics,10 pyrazines,41 alkenes and alkanes,15 aldehydes and ketones,8 heterocyclic compounds,and 4 other substances.The fire ring of Daqu detected 57 aroma compounds,mainly aromatic and alkenes/alkanes;the outer layer detected 52 aroma compounds,primarily aromatic,alkenes/alkanes,and pyrazines;the core detected the fewest,with 49 aroma compounds,mainly aromatic,alkenes/alkanes,and pyrazines.［Conclusion ］ The fire ring and outer layer of Daqu are the main sources of aromatic compounds in Fuyu flavor Baijiu.