The Glasgow Prognostic Score (GPS) is an inflammation-based cumulative prognostic score calculated from C-reactive protein (CRP) and albumin levels. The aim of the present study was to assess the value of the GPS as a prognostic tool in advanced esophageal cancer patients undergoing radiation therapy. The medical records of 90 patients with advanced esophageal cancer who had been treated with radiation therapy were reviewed retrospectively. Patients with both elevated CRP (>1.0 mg/dL) and hypoalbuminemia (<3.5 g/dL) were assigned a GPS of 2 ; patients who presented with one of these biochemical abnormalities were assigned a GPS of 1 ; and patients with normal CRP and albumin levels were assigned a score of 0. The median survival time in patients with a GPS of 0, 1, and 2 was 640, 394, and 222 days, respectively. A GPS of 2 was associated with shorter overall survival (OS). Multivariate analyses were used to evaluate factors affecting OS and revealed that a GPS of 2 (hazard ratio [HR] 1.897, 95% confidence interval [CI] 1.032.3.484, P=0.0391) was an independent prognostic factor for shorter OS. Eastern Cooperative Oncology Group performance status (ECOG-PS) was not a significant independent predictor of survival (HR 1.694, 95% CI 0.726-3.955, P=0.2229). These findings suggest that the GPS predicts OS in advanced esophageal cancer patients undergoing radiation therapy.