BACKGROUND Serum tumor markers including AFU, AFP, CEA, CA199, CA125 and CA724, are of great importance in the diagnosis, prognostic prediction and recurrence monitoring of gastrointestinal malignancies. However, their significance in gastric cancer (GC) patients with neoadjuvant therapy (NCT) is still uncertain. The aim of this study was to evaluate the predictive value of these six tumor markers in locally advanced GC patients who underwent NCT and curative surgery. METHODS In total, 290 locally advanced GC patients who underwent NCT and D2 radical gastrectomy were retrospectively analyzed. Data on their tumor markers before (pre-) and after (post-) NCT and pathological characteristics were extracted from the database of our hospital. The optimal cutoff values of the six tumor markers were calculated by the ROC curve and Youden index. Their predictive significance was analyzed and survival curves for overall survival (OS) were obtained by the Kaplan-Meier method. Associations between categorical variables were explored by the chi-square test or Fisher's exact test. Multivariate analyses were performed by the Cox regression model. RESULTS Pre- and post-CA199, -CA125 and -CA724 could predict overall survival (all P < 0.05), but only the change (diff-) of CA199 was related to prognosis (P = 0.05). In the multivariable analysis, pre- (P = 0.014) and post-CA724 (P = 0.036) remained significant, though diff-CA724 was not an independent prognostic factor (P = 0.581). In addition, pre- and post-CA199, -CA125 and -CA724 were associated with lymph node metastasis (N- vs N+) and pathological stage (I-II vs III) (all P < 0.05). Moreover, post-CA724 was related to the vascular or lymphatic invasion (P = 0.019), while pre-CA724 was not (P = 0.082). However, AFU, AFP and CEA showed no association with survival (P > 0.05). CONCLUSIONS CA724 is an independent factor for prognosis and could be used to predict ypN and ypTNM stage in locally advanced GC patients undergoing NCT and curative resection.