Objective To compare and analyze the effect of different irradiation field for postoperative lower thoracic esophageal carcinoma on survival rate, and compare toxicities of two groups. Methods We retrospectively analyzed 103 patients who underwent radical resection of lower thoracic esophagus carcinoma and had postoperative radiotherapy indication. Patients were devided into two groups, the extensive portal group and the regional portal group. All the patients underwent postoperative radiation four weeks after surgery. The radiation dose was from 45 to 54 Gy, and the medium was about 50 Gy. Results Grade≥2 gastrointestinal reactions in the regional group was significantly lower than that of the extensive group, with a statistically significant difference(P<0.05). For the entire group, the 1, 3 and 5 years survival rate of whole cases was 91.3%, 50.5%, 32.0% respectively. The 1, 3 and 5 years survival rate of the extensive group was 91.2%, 49.1%, 31.6% respectively, and 91.3%, 52.2%, 32.6% respectively in the regional group (not significant). Conclusion Using a regional portal in postoperative RT for lower esophageal carcinoma is not associated with compromised survival compared with extensive portal RT and adverse reactions were well tolerated.