Background: Five-year overall survival rate of TESCC after surgery is low (approximately 30% to 60%), so it is meaningful to discuss the significance of PORT. Methods: We retrospectively collected the data of 227 patients with PT3N0M0 esophageal cancer (EC). The failure pattern after surgery was analyzed. Difference of adjuvant PORT in patients with PT3N0M0 TESCC and the appropriate population were explored based on the relevant studies. Results: There were 58 cases with intrathoracic locoregional recurrence (LRR) after radical surgery and 27 cases with distant metastasis, including 10 cases of recurrence. The recurrence rate of mediastinal lymph nodes in the thoracic cavity was 50.0%. Univariate analysis revealed that compared with patients with middle and lower thoracic EC, the 3/5-year survival rate of patients with upper thoracic EC was significantly lower, accompanied with remarkably higher thoracic LRR. Compared with those with moderately-and well-differentiated TESCC, the 3/5-year survival rate of patients with poorly differentiated TESCC was significantly lower, whereas the distant metastasis rate was notably higher. Multivariate analysis revealed that different lesion locations and different pathologic differentiation were the independent prognostic factors. The lesion location and degree of differentiation were the independent influencing factors for thoracic LRR and distant metastasis, respectively. Conclusion: The intrathoracic LRR is the major failure pattern for patients with PT3N0M0 TESCC after conventional two-field lymphadenectomy. In addition, recurrence rate of PT3N0M0 TESCC was significantly higher in upper thoracic EC than in middle and lower thoracic EC. PORT is recommended to patients with PT3N0M0 upper TESCC.