It is important to evaluate the curability and avoid unnecessary exploratory operations for gastric and gastroesophageal junction adenocarcinoma. The aim of this study was to evaluate the factors that result in disease being incurable by operation.310 cases of T3-4 gastric and gastroesophageal junction adenocarcinoma were analysed retrospectively, which included 141 cases with radical operation and 169 cases who were surgically incurable. We analysed T stage (unresectable T4 tumour), N stage (unresectable lymph node), peritoneal metastasis, and distant metastasis as influencing factors. Chi square tests and logistic regression were performed to analyse the associations between curability, T stage, N stage, peritoneal metastasis, or distant metastasis and the clinicopathological data.For oesophageal involvement, T stage was associated with curability. Cardiac involvement and Borrmann type were associated with T stage. For oesophageal involvement, T stage were associated with N stage. For gastric body involvement, oesophageal involvement and T stage were associated with peritoneal metastasis. Gastric antrum involvement was associated with distant metastasis.Factors that influence surgical incurability should be analysed pre-operation. Resectability should be evaluated according to these factors and imaging analysis.