OBJECTIVE: The study aims to evaluate the role and mechanism of action of vitamin C as an anti- Epstein-Barr virus (EBV) and papillary thyroid carcinoma (PTC) therapeutic agent. METHODS: The PTC/EBV-associated genes were obtained by intersection and further screen out hub genes to construct a prognostic model. The relationship between PTC/EBV-related genes and core genes and immune infiltration was analyzed, respectively. Finally, the core targets of vitamin C against PTC/EBV were screened, and the binding sites were determined by molecular docking with vitamin C. RESULTS: The diagnostic efficiency and prognostic value of this model was good. The prognostic model performed well in male, female, classical, T3-4, N0, and N1 subgroups. Core genes STAT1 and APOE were highly expressed and FGF7 was lowly expressed in PTC. The core genes STAT1, APOE and FGF7 were significantly correlated with a variety of immune cells. 263 vitamin C-related targets were screened by the database, and 11 cross genes between vitamin C and PTC/EBV were identified. 4 molecular targets with the best performance, LGALS3, MMP9, CTSB and CTSS, were identified by topological analysis, and the binding energies were all CONCLUSIONS: Our prognostic model has good diagnostic and prognostic effects and has potential value of basic research. This study for the first time revealed the related molecular functions of vitamin C and the molecular targets for the treatment of PTC/EBV.