Objective To compare the effects of roasting and microwave conditions on odor compounds in walnut oil.Methods Identification of odor compounds in roasted walnut oil (140 ℃ roasting for 15 and 30 min; 160 ℃ roasting for 15 and 30 min) and microwaved walnut oil (700 W for 1, 3, 5, and 7 min) is performed by gas chromatography-mass spectrometry (GC-MS).Results A total of 74 odor compounds are identified, and the mass fraction of odor compounds gradually rises with increasing roasting temperature and microwave time. Aldehydes and heterocycles are the most dominant odor compounds in walnut oil. The 3-methyl butanal, pentanal, phenylacetaldehyde, 2,3-butanedione, 2,3-pentanedione, 2-pentylfuran, and 2-ethyl-6-methylpyrazine are determined to be the key odor compounds in roasted walnut oil (160 ℃ roasting for 30 min) and microwaveable walnut oil (700 W for 7 min). The roasted walnut oil (160 ℃ roasting for 15~30 min) and microwave walnut oil (720 W for 7 min) have the strongest odor, followed by roasted walnut oil (140 ℃ roasting for 30 min) and microwave walnut oil (720 W for 3~5 min); While roasted walnut oil (140 ℃ roasting for 15 min) and microwave walnut oil (720 W for 1 min) have the weakest odor.Conclusion Roasting at high temperature for a long time (160 ℃ roasting for 30 min) promotes the formation of heterocyclic compounds more effectively, while microwave treatment can achieve a comparable flavor intensity in a shorter time (7 min). Both methods are effective in enhancing the odor intensity of walnut oil.