Objective: To evaluate the prognostic value of modified Glasgow prognostic score (mGPS) asssessed prior to anticancer treatment in patients with esophageal squamous cell cancer (ESCC).Methods: A comprehensive search through PubMed, EMBASE, Web of Science and The Cochrane Library databases was performed to identify potential studies exploring the prognostic value of baseline mGPS in patients with ESCC. We combined the hazard ratios (HRs) with 95% confidence intervals (CIs) to assess the association of mGPS with overall survival (OS).Results: A total of 10 studies including 3415 patients were analyzed and all patients were from Japan or China. A significant correlation between elevated mGPS and poor OS (HR = 1.66, 95% CI: 1.14-2.41, P = 0.008) was observed. Subgroup analyses suggested that the country and therapy method may affect the effect of mGPS on predicting OS in ESCC and patients with mGPS 1 or two had poorer OS compared with those with mGPS 0 (HR = 2.91, 95% CI: 1.74-4.87, P<0.001; HR = 2.39, 95% CI: 1.44-3.97, P = 0.001).Conclusions: Baseline mGPS might serve as a promising indicator for the OS in Chinese and Japanese patients with ESCC. More well-designed prospective studies with large samples are needed to verify our findings.