Display omitted •Effects of tebuconazole on wine quality were investigated at enantiomeric level.•The influence of the enantiomers was different for ML and CS wine components.•HS-SPME-GC-MS and GC-IMS were used to analyze the volatile flavor compounds.•Changes in wine components led to changes in wine flavor and appearance.•The racemate and separate tebuconazole enantiomers affect wine quality differently. The impact of chiral tebuconazole on the flavor and appearance of Merlot and Cabernet Sauvignon wines were systematically studied. Gas chromatography-ion mobility spectrometry and headspace-solid phase microextraction coupled with gas chromatography mass spectrometry qualitatively and quantitatively identified the flavor components, and a photographic colorimeter was used for color attribute analysis. Tebuconazole enantiomers had different effects on the flavor and appearance of young wines, especially R-tebuconazole. The flavor differences were mainly manifested in fruity and floral characteristics of the wine due to changes in the concentrations of acids, alcohols, and esters; R-tebuconazole alters the concentrations of key flavor compounds to the greatest extent. Tebuconazole treatment changes the color of young wines, with the final red shade of wine being control group > rac-tebuconazole ≥ S-tebuconazole > R-tebuconazole. Since chiral tebuconazole negatively alters wine, grapes treated with chiral pesticides should be subject to stricter quality control during processing.