The odor quality of potato tuber after processing is an important index to evaluate the quality of processed products. Analyzing odor quality of potato tuber after processing can not only improve the evaluation system of potato tuber flavor, but also provide a basis for breeding varieties with excellent flavor. In this study, the tubers of 20 potato varieties (lines) were used as materials, which were steamed at 110℃ and baked at 250℃. The volatile flavor compounds produced from these cured tubers were identified by the headspace solid phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS), and the correlation between volatile flavor components was analyzed. Combined with the sensory evaluation of odor quality, the relative odor activity value (ROAV) analysis, partial least squares-discriminant analysis (PLS-DA), and principal component analysis (PCA) were performed for volatile flavor compounds. After steaming at 110℃, the content of aldehydes was the highest among the volatile flavor components of 20 varieties (lines). The content of aldehydes was significantly positively correlated with pyrazines, and the content of esters was significantly negatively correlated with hydrocarbons. After baking at 250℃, the content of esters was the highest among the volatile flavor components of 20 varieties (lines). There was a significant positive correlation between aldehydes and furans, ketones and hydrocarbons, acids and other heterocycles, respectively. The content of ketones was significantly negatively correlated with furans, and the content of aldehydes was significantly negatively correlated with esters and ketones. After steaming, there were 39 key flavor substances with ROAV>1 in tubers. PLS-DA results indicated that these key flavor substances with VIP>1 included lauraldehyde, n-tetradecane, palmitic acid, phenylacetaldehyde, n-cetane, 2-amino-5-methylbenzoic acid, n-nonaldehyde, decylaldehyde, n-dodecane, n-octanaldehyde and p-xylene. Five principal components were extracted by PCA analysis, and the cumulative contribution rate reached 86.248%. After baking, there were 45 key flavor substances with ROAV>1 in tubers. PLS-DA results indicated that these key flavor substances with VIP>1 included n-cetane, n-nonaldehyde, capric aldehyde, n-tetracetane, palmitic acid, n-dodecane, lauraldehyde, benzaldehyde and geraniylacetone. Four principal components were extracted by PCA analysis, and the cumulative contribution rate reached 78.102%. The laural, phenylacetaldehyde, n-nononal, capric aldehyde, n-tetradecane, n-cetane, and palmitic acid were the markers of excellent odor quality of steamed potatoes. The benzaldehyde, n-nonyl aldehyde, capric aldehyde, lauryl aldehyde, n-tetradecane, n-cetane, palmitic acid, and geranyl acetone were the markers of excellent odor quality of baked potatoes. The potato varieties with excellent odor quality after steaming and baking were sante Malta, H0916, H0933, H0951, and Gannong milk sweet potato.