Abstract: To investigate the effects of six different edible oils (soybean oil, sunflower oil, camellia oil, palm oil, perilla oil, and sesame oil) applied by brushing onto grass carp pieces, this study evaluated their color, texture, sensory characteristics, volatile flavor compounds, and fatty acid composition after baking. The results showed that brushing with vegetable oils significantly improved the overall acceptability of the baked fish. A total of 42 volatile flavor compounds were detected, with 8 identified as key compounds, primarily aldehydes such as (Z)-2-nonenal, trans-2-decenal, trans,cis-2,4-decadienal, and trans,trans-2,4-decadienal. The sesame oil treatment imparted a rich roasted aroma due to its characteristic pyrazines, achieving the highest overall sensory score and the greatest variety of key volatile flavor compounds. In contrast, sunflower oil had the least impact on the inherent flavor of the fish, better preserving its original taste. Correlation analysis revealed that nonanal, a common flavor compound, was positively correlated with multiple PUFAs (C18:3n6, C20:3n6, C22:6n3) and SFAs (C11:0, C14:0, C15:0, C20:0), whereas 2-heptenal and benzyl alcohol exhibited negative correlations with the same set of SFAs (C11:0, C14:0, C15:0, C20:0). This elucidates the relationships between several key flavor substances and specific fatty acids in the fish fillets. The findings of this study provide a scientific basis and theoretical guidance for optimizing the flavor quality of grilled fish products through targeted oil selection.