Objective To explore the efficacy of consolidation chemotherapy after radical radiotherapy and chemotherapy in stage Ⅲ-ⅣA esophageal squamous cell carcinoma (ESCC) patients in the real world. Methods The clinical data of 139 patients with stage Ⅲ-ⅣA ESCC who underwent radical radiotherapy and chemotherapy from January 1, 2018 to December 31, 2022 in Hefei Cancer Hospital, Chinese Academy of Sciences were retrospectively analyzed. Patients were divided into a control group (n=85) and a consolidation chemotherapy group (n=54) based on whether they underwent consolidation chemotherapy after radical radiotherapy and chemotherapy. The objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) between the two groups were compared. The Kaplan-Meier method was used to draw survival curves and log-rank tests were conducted. The Cox proportional risk model was used for univariate and multivariate analysis. Results The ORR of the control group and the consolidation chemotherapy group were 44.71% (38/85) and 66.67% (36/54), respectively, with a statistically significant difference (χ2=5.54, P=0.018); the DCR were 70.59% (60/85) and 87.04% (47/54), respectively, with a statistically significant difference (χ2=5.04, P=0.025). The median PFS of the two groups of patients were 9.0 and 13.1 months, respectively, with a statistically significant difference (χ2=12.74, P<0.001); the median OS were 15.0 and 20.6 months, respectively, with a statistically significant difference (χ2=24.75, P<0.001). The median OS of ESCC patients in two subgroups of cT3-4N1-3M0 were 16.0 and 30.8 months, respectively, with a statistically significant difference (χ2=23.49, P<0.001). Univariate analysis showed that tumor length (HR=1.57, 95%CI: 1.04-2.36, P=0.032), objective response (HR=0.08, 95%CI: 0.04-0.17, P<0.001), and consolidation chemotherapy (HR=0.32, 95%CI: 0.20-0.51, P<0.001) were all influencing factors for OS in ESCC patients undergoing radical radiotherapy and chemotherapy in stages Ⅲ-ⅣA. Multivariate analysis showed that tumor length (HR=1.59, 95%CI: 1.05-2.43, P=0.030), objective response (HR=0.05, 95%CI: 0.02-0.10, P<0.001), and consolidation chemotherapy (HR=0.22, 95%CI: 0.13-0.36, P<0.001) were all independent influencing factors for OS in stage Ⅲ-ⅣA ESCC patients undergoing radiotherapy and chemotherapy. In terms of safety, the consolidation chemotherapy group experienced 7 adverse reactions mainly gastrointestinal reaction and leukopenia, including 5 cases of grade 1-2 and 2 cases of grade 3-4; 22 cases of adverse reactions occurred in the control group including 16 cases of grade 1-2 and 6 cases of grade 3-4 mainly including neutropenia, thrombocytopenia, anemia and digestive tract reaction. The incidence rates of adverse reactions in the two groups were 12.96% (7/54) and 25.88% (22/85), respectively, with no statistically significant difference (χ2=3.34, P=0.068). Conclusion After radical radiotherapy and chemotherapy, consolidation chemotherapy can significantly improve the prognosis of stage Ⅲ-ⅣA ESCC patients, and the overall adverse reactions are controllable.