Abstract: Objective To establish ERCC1 overexpression cell line and evaluate the cytotoxic effect of oxaliplatin.Methods After RNA isolation from colorectal tumor,cDNA synthesis,ERCC 1 PCR product was obtained,ERCC 1 was transfected to UV20 cell line using gateway technique.Cytotoxic effect of oxaliplatin was evaluated by cell inhibition assay.Results UV20-ERCC 1 cell line was established successfully and ERCC 1 overexpression in UV20-ERCC1 was confirmed by Westem blot.Positive relationship between resistance to Oxaliplatin and ERCC 1 expression level was measured by SRB assay.Conclusion Destiny vector containing ERCC1 is established by gateway technique and a feasible method can be used to study on function of ERCC1 gene.