The results of treatment of 54 esophageal carcinomas managed with low-dose-rate telecobalt therapy (LDRT) as a boost were compared with those of 89 esophageal carcinomas treated with conventionally fractionated irradiation alone (CFI). The LDRT (1 Gy/hr, 5-7 Gy/day, to a total dose of 14-20 Gy) was boosted about 10 days after the CFI dose of 60 Gy. Although the LDRT group included more advanced cases than the CFI group, local effects and survival rate of the LDRT group, especially those with tumorous X-P and serrated types, were better than those of the CFI group. Late complications were more severe in the LDRT group. However, they were acceptable when the total dose in the LDRT group was brought under 80 Gy.