Long non-coding RNA (lncRNA) LINc00473 plays a carcinogenic role in a variety of different tumor types. Nevertheless, the mechanisms through which LINc00473 regulates the radiosensitivity of esophageal squamous cell carcinoma (EScc) cells remains elusive. In the present study, reverse transcription-quantitative PcR was used to quantify the expression of LINc00473, microRNA (miRNA/miR)-497-5p and cell division cycle 25A (cdc25A) in EScc tissues. The association between LINc00473 expression and the clinicopathological characteristics of patients with EScc was also assessed. Furthermore, cell counting kit-8 and colony formation assays were carried out to monitor the proliferation of EScc cells exposed to X-ray radiation. A dual-luciferase reporter assay was also conducted to analyze the interaction between LINc00473 and miR-497-5p, as well as the interaction between CDC25A and miR-497-5p. The findings of the present study demonstrated that in EScc tissues and cells, the expression levels of LINC00473 and CDC25A were significantly upregulated, while the expression of miR-497-5p was downregulated. The high expression level of LINc00473 was associated with a higher T stage, lymph node metastasis stage and a lower tumor differentiation grade in patients with EScc. Following irradiation, transfection with miR-497-5p mimics reduced the promoting effect of LINc00473 overexpression on EScc cell proliferation, and partially impeded the resistance of EScc cells to X-ray radiation induced by LINc00473 overexpression. Moreover, transfection with miR-497-5p inhibitors partially alleviated the inhibitory effects of LINc00473 knockdown on cellular proliferation, and partly reversed the sensitivity of cells to X-ray irradiation induced by LINc00473 knockdown. Furthermore, it was confirmed that miR-497-5p was able to bind LINc00473 and the 3'-untranslated region of CDC25A. On the whole, the findings of the present study demonstrate that LINc00473 reduces the radiosensitivity of EScc cells by modulating the miR-497-5p/cdc25A axis.