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To investigate the effect of enzymatic digestion of different proteases on the volatile flavor components of soybean meal, four proteases (alkaline protease, neutral protease, papain, flavor protease) were selected to enzyme soybean meal, using a headspace-gas chromatography-ion mobility spectroscopy (HS-GC-IMS) and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) to analyze volatile flavor composition of different soybean meal hydrolysates (SMH), combined with the principal component analysis (PCA), heatmap clustering, and orthogonal partial least squares-discriminant analysis (OPLS-DA) to analyze the different SMH. The results showed that the volatile flavor components of alkaline protease, neutral protease, papain and flavor protease were quite different. HS-GC-IMS identified 84 volatile components, and screened 33 differential flavor substances, which found that the content of ketones and aldehyde, alcohols and esters were increased significantly after enzymatic digestion. The PCA results indicated significant differences in flavor between different SMH. Finally, volatile compounds with large contributions were selected by OPLS-DA, and reliable models used to identify SMH were constructed. HS-SPME-GC-MS detected 103 different flavor substances that could be used to distinguish different SMH. The volatile compounds such as aldehyde, alcohols, and ketones made major contributions to the formation of SMH flavor, which clarified the reasons for the formation of some flavor compounds. PCA and cluster heat map results showed that the enzyme digestion of different proteases had a significant influence on the type and content of volatile flavor substances of soybean meal, among which, flavor protease and papain showed the most significant flavor improvement of soybean meal.