Abstract: This study aimed to identify optimal drying conditions for shelled Macadamia nuts and to investigate the mechanisms underlying the formation of volatile compounds during the drying process, thereby offering a theoretical framework for quality control in the initial processing of Macadamia nuts. The study utilized six primary varieties of Australian Macadamia nuts cultivated in Guangxi—namely Gui Re 1 (designated as "1HAO"), 695, OC, H2, A38, and A16—as experimental subjects. Gas chromatography-ion mobility spectrometry (GC-IMS) was employed to detect and analyze the volatile organic compounds present in Macadamia nuts subjected to drying at 40 ℃ for one week, 50 ℃ for 96 hours, and 60 ℃ for 48 hours. The volatile components generated during the drying process were examined through the integration of chemical pattern recognition, sensory evaluation, and relative odor activity value (ROAV) analysis, with the aim of elucidating the differences in volatile components among the various nut varieties. The analysis identified a total of 32 volatile compounds across the three drying treatments, comprising 11 alcohols, 7 aldehydes, 5 ketones, 1 acid, 6 esters, and 2 additional substances. Notably, the concentrations of alcohols and ketones were higher, whereas the aldehydes were present in lower concentrations. The analysis of variance revealed statistically significant differences (P<0.05) in ester concentrations across the three treatments. However, the extent of differences in other categories varied among the treatments. Drawing on the characteristics of volatile components and existing literature, it was hypothesized that the volatile substances produced during the drying process primarily originated from lipid oxidation and enzymatic reactions. The principal flavor compound, 2,3-butanedione, known for its creamy aroma, exhibited significant differences between the 40 ℃ treatment group and the 50 ℃ and 60 ℃ treatment groups. However, no significant difference was observed between the 50 ℃ and 60 ℃ treatment groups. Sensory evaluation and energy consumption analysis indicated that the 50 ℃ treatment most effectively enhanced the texture, aroma, and overall acceptability of the nuts, without introducing significant adverse flavors. Consequently, when considering both quality and energy consumption factors, the optimal drying process for shelled Macadamia nuts was identified as 96 hours at 50 ℃. Utilizing the GC-IMS data under this condition, combined with chemical pattern recognition and ROAV analysis, eight distinctive volatile components were identified. Among these, isobutanol, isoamyl alcohol, and acetic acid emerged as the principal compounds that significantly influenced the overall flavor profile. Through the application of OPLS-DA, in conjunction with clustering heatmaps and analysis of variance, it has been demonstrated that acetic acid was a distinctive component of A38. Similarly, 2,5-dimethylfuran was identified as a shared characteristic component of both 1HAO and OC. The compounds ethyl acetate, isobutanol, and propanol were distinctive to H2, while isoamyl alcohol was specific to 695, ethanol to A16, and isopropanol to OC. The generation of volatile compounds during the drying process of various Macadamia nut varieties may be influenced by distinct metabolic pathways, which were in turn affected by variations in the internal content of substances such as sugars and amino acids. Nonetheless, the precise relationship between volatile components and intrinsic substances necessitated further investigation at the level of metabolic pathways.