To determine if IGFBP-3 participates in Nimotuzumab-enhanced radiosensitivity of ESCC cells with high expression of EGFR, we first knocked down the levels of IGFBP-3 in KYSE30 cells by specific shRNA against IGFBP-3 gene and found that silence of IGFBP-3 dramatically reduced ESCC cell radiosensitivity. This evidence concerns the gene IGFBP3 and esophageal squamous cell carcinoma.