Purpose: Preoperative therapy improves overall survival (OS) after surgery in patients with adenocarcinoma of the esophagogastric junction (AEG). We aimed to retrospectively analyze whether preoperative chemoradiotherapy (CRT) could improve the prognosis of patients with locally advanced Siewert II and III AEG comparing with preoperative chemotherapy alone (CT). Patients and methods: From March 2012 to December 2015, 170 patients with locally advanced (cT3-4NxM0) Siewert II and Ill AEG were treated with preoperative CRT or CT in Hebei Medical University Fourth Hospital, and 123 patients were included in this study to compare the effects of preoperative CRT with CT. Results: RO resection rate was 96.7% in CRT group and 82.5% in CT group (P = .016). The pathological complete response was 16.7% after CRT group and 3.2% after CT (P = .015). The median follow-up time was 20 months. The 1- and 3-year OS were 89.4%, 79.2% in CRT group and 88.2%, 58.0% in CT group (P = .016; HR = 0.40, 95% confidence interval 0.21-0.76). The 1- and 3-year PFS were 87.3%, 73.5% in CRT group and 72.8%, 42.8% in CT group (P = .014; HR = 0.46, 95% confidence interval 0.24-0.86). Multivariate analysis showed that clinical T stage, adjuvant chemotherapy cycles and histologic differentiation were shown to be the independent prognostic factors for OS, and postoperative pathologic N stage was shown to be the independent prognostic factor for PFS. Conclusion: For the patients with locally advanced AEG, the addition of radiotherapy to preoperative chemotherapy can improve survival with safety, but is not an independent prognostic factor for OS and PFS. (C) 2018 Elsevier Ltd, BASO similar to The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.