The overall efficacy of neoadjuvant chemotherapy for locally advanced gastric cancer has been recognized. However, neoadjuvant chemotherapy is ineffective in a subset of patients due to tumor heterogeneity. The tumor regression grade (TRG) has unique advantages in assessing the efficacy of neoadjuvant chemotherapy for gastric cancer. Nonetheless, since TRG is dependent on postoperative pathology, it becomes a significant topic today to mine TRG predictors to more accurately select appropriate patients for neoadjuvant chemotherapy. Therefore, to understand the relevant research progress and current research challenges of TRG predictors after neoadjuvant chemotherapy for gastric cancer from the aspects of biomarkers, immunity, inflammatory indicators, body composition, imaging indicators, etc., is conducive to further clinical research and practice.