<p>The variety of raw materials has a significant influence on the quality of fermented foxtail millet beverages produced using liqueur koji. This study analyzed the taste components, aroma components, and antioxidant activity of various liqueur koji fermented foxtail millet beverages. Results from the electronic nose and electronic tongue indicated notable differences between waxy and japonica varieties. Sensory evaluations revealed that QG (Qiangu 1, waxy) and ZS (Zhesu 3, waxy) received lower comprehensive scores, while ZZ (Zhangzagu 13, japonica) achieved the highest sensory scores. The organic acids in the six millet beverages were predominantly lactic acid and succinic acid, identified as the main taste-active compounds. Notably, ZZ exhibited the highest total free amino acids, essential amino acids, sweet amino acids, and functional amino acids. In contrast, QG and ZS displayed the lowest amino acid contents. A total of 50 volatile compounds were detected across the six millet beverages, with 20 compounds identified as potential biomarkers for distinguishing among the six foxtail millet varieties. Seventeen volatile compounds were characterized by odor activity values &gt; 1. Esters, aldehydes, and alcohols emerged as the primary contributors to aroma, with varying effects on the aroma profile of each variety. “Fruity” aroma was the most pronounced, followed by “Floral” and “Fatty” aromas. Additionally, ZZ demonstrated the highest polyphenols, flavonoids, and peptides, along with the strongest DPPH and ABTS free radical scavenging activities. The waxy variety exhibited the highest mineral content. Consequently, this study suggested that ZZ is particularly suitable for brewing liqueur koji foxtail millet beverages. These findings can provide valuable insights for selecting appropriate varieties for millet-fermented beverages.</p> Graphical abstract <p></p>