ObjectiveTo explore the distribution characteristics of traditional Chinese medicine （TCM） syndromes in postoperative gastric cancer patients， and to analyse the factors associated with yang deficiency syndrome and its severity. MethodsTotally， 173 patients who underwent postoperative gastric cancer surgery and were treated in four centers nationwide from February 22， 2022 to March 21， 2023， were enrolled. General information and TCM syndromes were collected， and Diagnostic Scale for Yang Deficiency Syndrome in Gastric Malignancies was filled in. The frequency of TCM syndromes after gastric cancer surgery was analyzed， and univariate analysis and multivariate logistic regression analysis were performed on the related factors of yang deficiency syndrome versus non-yang deficiency syndrome and between different severity of yang deficiency syndrome. ResultsThe most common syndrome after gastric cancer surgery was qi deficiency （95 cases， 54.91%）， followed by yang deficiency （87 cases， 50.29%）. Patients with yang deficiency syndrome were often suffered from qi deficiency， qi stagnation， and phlegm dampness syndrome. Comparing yang deficiency syndrome with non-yang deficiency syndrome， univariate analysis showed that history of alcohol consumption， pathological stage， degree of differentiation， Lauren grade， signet ring cell carcinoma， vascular cancer thrombus， and nerve invasion were statistically significant （P＜0.05）； and multivariate logistic regression analysis showed that history of alcohol consumption， signet ring cell carcinoma， pathological stage Ⅲ， Ⅳ， and vascular cancer thrombus may be correlated with yang deficiency syndrome in postoperative gastric cancer patients （P＜0.05）. The univariate analysis showed that age， pathological stage， precancerous lesions， and body mass index grade were significantly different when compared between mild and severe yang deficiency syndrome （P＜0.05）； multivariate logistic regression analysis showed that age， low body weight， and pathological stage Ⅲ and Ⅳ might be correlated with severe yang deficiency syndrome after gastric cancer surgery （P＜0.05）. ConclusionQi deficiency and yang deficiency are common TCM syndromes in postoperative patients with gastric cancer. Alcohol consumption history， pathological staging （stage Ⅲ and Ⅳ）， signet ring cell carcinoma， and the presence of vascular cancer thrombus may be correlated with the occurrence of yang deficiency syndrome， and higher age， low body weight， and pathological staging （stage Ⅲ and Ⅳ） may be the correlates of severe yang deficiency syndrome.