Background: The coronavirus disease 2019 (COVID-19) pandemic disrupted healthcare and worsened quality of life (QOL). Advanced esophageal cancer is often accompanied by malnutrition and poor QOL; chemoradiotherapy (CRT) remains the mainstay of treatment.We evaluated nutrition and QOL pre- and post-CRT immediately before and during the pandemic. Methods: Patients with esophageal cancer who underwent neoadjuvant or definitive CRT between April 2019 and December 2020 were enrolled. Disease severity, treatment timing, and outcomes were compared for cohorts treated pre-COVID-19 and during COVID-19. Nutritional status was measured with the Patient-Generated Subjective Global Assessment (PG-SGA). QOL was measured with the Mandarin Chinese version of the European Organization for Research and Treatment of Cancer core questionnaire (EORTC QLQ-C30) and the esophageal site-specific module (QLQ-OES18). In the pandemic cohort, pre-/post-CRT paired analyses were performed. Results: Eighty-four patients were enrolled. The median diagnosis to treatment interval lengthened during COVID-19 (17.8 days vs. 24.2 days, p=0.04). Among the patients treated during the COVID-19 pandemic, nutritional status improved significantly following CRT (p=0.003). In the EORTC QLQ-C30, post-CRT scores for global health status (p<0.01) and emotional functioning (p<0.01) showed significant improvement. Additionally, symptom scores, including fatigue (p=0.02) and nausea and vomiting (p=0.02), decreased. However, financial difficulties worsened after CRT (p=0.02). In the EORTC QLQ-OES18, post-CRT symptom scores for eating (p<0.01), reflux (p=0.03), and pain (p<0.01) showed significant improvement. Conclusion Despite COVID-19-related delays, CRT enhanced nutrition, global health, and symptom control in esophageal cancer, although financial burdens increased. Integrating socioeconomic support with oncologic care is vital during health crises.