Objective: To observe the effect of Kang’ai Injection (康艾注射液, KAI) on serum level of soluble interleukin-2 receptor (sIL-2R) and vascular endothelial growth factor (VEGF) in patients with esophageal carcinoma (EC) during radiotherapy (RT), and to investigate its synergistic effect with RT and its influence on immunological function of the body.Methods: One hundred and seventy patients with EC, who had missed the chance of surgical operational therapy, were assigned to the treated group (90 cases) and the RT group (80 cases), and at the same time a control group consisting of 80 inpatients without tumors was set up. Patients in the RT group were treated with RT alone but KAI was given additionally to those in the treated group, with 50 ml given once per day via intravenous dripping, 15 days as one course, and 2 courses administered in total. The immediate therapeutic efficacy and changes of serum sIL-2R and VEGF levels were observed, and the effect of KAI on patients’ quality of life (QOF) was evaluated by Karnofsky scoring. Results: In 16 patients of the treated group it was completely remission (CR), in 54 partially remission (PR), in 18 it was stabilized disease (SD) and in 2 progressive disease (PD), with the total effective rate (CR+PR) as 77.8%, while in those of the control group it was 12, 46, 18, 4 and 72.5%, respectively, the immediate therapeutic efficacy in the treated group was somewhat better than that in the RT group, but showed no statistical significance (P>0.05). Serum levels of sIL-2R and VEGF in all the patients before treatment were higher than those in the control group, which were decreased after treatment in both groups (P<0.05), but the improvement in the treated group was better than that in the RT group, showing significant difference ( P<0.05), and patients’ QOF improved more significantly in the former as well (62.2% vs 400%, P<005). Conclusion: KAI in combination with RT in treating patients with EC could enhance the immunological function of patients, improve their QOF and enhance their sensitivity to RT. Objective: To observe the effect of Kang’ai Injection (KAI) on serum level of soluble interleukin-2 receptor (sIL-2R) and vascular endothelial growth factor (VEGF) in patients with esophageal carcinoma (EC) during radiotherapy (RT), and to investigate its synergistic effect with RT and its influence on immunological function of the body. Methods: One hundred and seventy patients with EC, who had missed the chance of surgical operational therapy, were assigned to the treated group ( 90 cases) and the RT group (80 cases), and at the same time a control group consisting of 80 inpatients without tumors was set up. Patients in the RT group were treated with RT alone but KAI was given more to those in the treated group with 50 ml given once per day via intravenous dripping, 15 days as one course, and 2 courses administered in total. The immediate therapeutic efficacy and changes of serum sIL-2R and VEGF levels were observed, and the effect of KAI on patients qual Results: In 16 patients of the treated group it was completely remission (CR), in 54 partially remission (PR), in 18 it was stabilized disease (SD) and in 2 progressive disease (PD), with the total effective rate (CR + PR) as 77.8%, while in those of the control group it was 12, 46, 18, 4 and 72.5%, respectively, the immediate therapeutic efficacy in the treated group was somewhat better than that in the group, but showing no statistical significance (P> 0.05). Serum levels of sIL-2R and VEGF in all the patients before treatment were higher than those in the control group, which were decreased after treatment both both groups (P <0.05), but the improvement in the treated group was better than that in the RT group, showing significant difference (P <0.05), and patients’ QOF improved more significantly in the former as well (62.2% vs 40  0%, P <005). Conclusion: KAI in combination with RT in treating patients with EC could enhance th e immunological function of patients, improve their QOF and enhance their sensitivity to RT.