Objective: Pretreatment systemic inflammation and nutrition-based prognostic indices (SINBPI) have demonstrated significance. This study investigated the prognostic value of pretreatment SINBPI for patients with oropharyngeal cancer and identified unfavorable prognostic markers. Methods:We retrospectively reviewed the data of 124 patients with oropharyngeal squamous cell carcinoma (OPSCC) who received definitive treatment between January 2010 and December 2018. The prognostic utility of the neutrophil-tolymphocyte ratio, platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), prognostic nutritional index, and high-sensitivity modified Glasgow prognostic score (HS-mGPS) was assessed for disease-free survival (DFS), diseasespecific survival (DSS), and overall survival (OS) using univariate and multivariate analyses.Results: Multivariate analyses revealed that human papillomavirus (HPV) status and HS-mGPS were significantly associated with DFS, DSS, and OS. Patients with a HS-mGPS of 2 had a significantly higher rate of treatment-related deaths than those with a HS-mGPS of 0 or 1. The combination of the HS-mGPS and PLR had more accurate predictive ability in DFS and OS compared with the HS-mGPS alone, and the combination of the HS-mGPS and LMR had more accurate predictive ability in DSS and OS. Conclusion:Our results indicated that the HS-mGPS was a useful prognostic marker for patients with OPSCC, and combined markers consisting of the HS-mGPS and PLR or LMR may provide more accurate prognostic predictions.