Objective To analyze the rule of lymph node metastasis in thoracic esophageal carcinoma,and to study the proper radiation target. Methods From September 1986 to December 1997,549 patients with esophageal carcinoma who had undergone radical reseetion were divided into surgery alone group (S,275 patients) or surgery plus radiotherapy group( S + R,274 patients). Radiotherapy was begun 3 to 4 weeks after operation. The radiation target included beth supra-clavicular areas and the entire mediastinum. The total dose was 50 Gy in 25 fractions over 5 weeks for the supra-clavicular areas and 60 Gy in 30 fractions over 6 weeks for the entire mediastinum. Results The 5-year overall survival of patients with lymph node metastasis in one anatomic site and two anatomic sites was 31.5% and 13.9% (P=0.013), respectively. For patients with > 2 positive nodes metastasis receiving surgery alone, the corresponding 5-year survival was 24.8% and 4.9% (P=0.046) ,respectively. The median number of dissected lymph nodes of the upper-,middle-and lower-segment esophageal carcinoma was 13,17 and 20, respectively. The rate of metastatic lymph node in the para-esophagus region was the highest(61.5%-64.9%) ,which was not different among the different primary sites(P=0.922). The anastomotic stoma recurrence rate of the upper-segment esophageal carcinoma was higher than that of the middle- or lower-segment carcinomas(16.7% ,3.1% ,and 7.7%, χ2=9.02,P<0.05). Conclusions For the thoracic esophageal carcinoma,the number of anatomic sites of lymph node metastasis is an important factor affecting the survival. The lower rate of lymph node metastasis of the upper segment esophageal carcinoma may be corrected with the less lymph node dissected. The rate of lymph node metastasis in para-esophageal region is not related with the lesion segment. The anastemotie stoma is an important radiotherapy target for upper segment esophageal carcinoma.