The aim of this study was to examine the prognostic factors and treatment outcomes of cervical esophageal carcinoma (CEC) patients who underwent definitive chemoradiotherapy (CRT). The clinical data of 175 biopsy-confirmed CEC patients treated with definitive CRT between April 2005 and September 2021 were retrospectively analyzed. The prognostic factors predicting overall survival (OS), progression-free survival (PFS), and local recurrence-free survival (LRFS) were assessed in uni-and multivariable analyses. The median age of the entire cohort was 56 years (range: 26–87 years). All patients received definitive radiotherapy with a median total dose of 60 Gy, and 52% of the patients received cisplatin-based concurrent chemotherapy. The 2-year OS, PFS, and LRFS rates were 58.8%, 46.9%, and 52.4%, respectively, with a median follow-up duration of 41.6 months. Patients’ performance status, clinical nodal stage, tumor size, and treatment response were significant prognostic factors for OS, PFS, and LRFS in univariate analysis. Non-complete treatment response was an independent predictor for poor OS (HR = 4.41, 95% CI, 2.78–7.00, p < 0.001) and PFS (HR = 4.28, 95% CI, 2.79–6.58, p < 0.001), whereas poor performance score was a predictor for worse LRFS (HR = 1.83, 95% CI, 1.12–2.98, p = 0.02) in multivariable analysis. Fifty-two patients (29.7%) experienced grade II or higher toxicity. In this multicenter study, we demonstrated that definitive CRT is a safe and effective treatment for patients with CEC. Higher radiation doses were found to have no effect on treatment outcomes, but a better response to treatment and a better patient performance status did.