Background Although epidermal growth factor receptor (EGFR) inhibitor treatment showed mod est response in several clinical trials in ESCC patients,it has been reported that the frequency of EGFR mutations vari ed largely.Objective The aim of this study was to investigate the existence of EGFR mutations in Chinese esophag eal squamous cell carcinomas.Methods Formalin-fixed paraffin-embedded (FFPE) surgically resected tumor samp les were obtained from 127 randomly selected Chinese patients with ESCC.The most common EGFR mutations,incl uding in-frame deletions in exon 19 and amino acid substitutions in exon 21,were detected by denaturing high perfor mance liquid chromatography (DHPLC) and direct sequencing simultaneously.KRAS mutations in codons 12 and 13 were detected by direct sequencing.Results: In the present study,L858R missense mutation of EGFR gene were fou nd in 8 out of 127 patients (6.3%) by DHPLC but no mutation was observed by direct sequencing.In addition,2 out of 127 (1.6%) K-RAS mutations were detected by direct sequencing.Conclusions The incidence of EGFR mutatio ns detected by DHPLC was relatively high but no mutations by direct sequencing in Chinese patients with ESCC.