Abstract: Objective: To observe the clinical results and acute side effects of three-dimensional conformal radiotherapy (3DCRT) for esophageal carcinoma. Methods: From July 2003 to March 2007, 100 patients with esophageal carcinoma received 3DCRT with a median prescription dose of 6400cGy (ranging from 5600cGy to 7000cGy), 200 cGy/per fraction, 1 fraction/per day, 5 fractions/per week. The clinical results and side effects were evaluated. Results: (1)Sixty-five patientshad complete remission(CR), and 34 patients had partial remission(PR). The overall response rate was 99% (CR+PR). (2)The 1-, 2-, and 3-year local control rates were 73.49%, 55.21% and 42.77%, respectively. The 1-, 2-, and 3-year over-all survival rates were 73.25%, 48.09% and 43.39%, respectively. The median survival time was 24 months. Multivariate analysis showed that aortic invasion and short term results were correlation factors. Aortic invasion was observed in 42 pa-tients. The 3-year survival rate was 35.25% in patients with aortic invasion, and 48.26% in patients without aortic inva-sion, respectively (P=0.0577). A total of 65 patients had CR and 34 patients had PR after radiotherapy, with a 3-year sur-vival rate of 50.27% and 31.08%, respectively(P=0.016 3). (3) Of these 100 patients, 49(49%) developed radiation pneu-monitis(RP): grade 1 in 27 patients, grade 2 in 16 patients and grade 3 in 6 patients. Acute radiation esophagitis was also observed: grade 0 in 18 patients, grade 1 in 50 patients, grade 2 in 24 patients and grade 3 in 8 patients. Conclusion: The technique of 3DCRT is an effective treatment for esophageal carcinoma and can improve the overall survival rate.Further studies should use a larger population and a longer follow-up to identify the long term effect of 3DCRT.