ObjectiveM26I，and provid a basis for further study on the relationship of DJ-1 ^M26I mutation and cell proliferation and apoptosis and establish transgenic animal model． Methods Using site-directed mutagenesis kit to make the 26th amino acid mutated，constructed pcDNA3. 1 /myc-His-DJ-1 and pcDNA3. 1 /myc-His-DJ-1 ^M26I recombinant expression vectors．And then transfected them into NIH3T3 cells respectively using lipofectamine． Cells were selected with G418 at the level of 500μg /ml． Stable clones were identified on the DNA，RNA and protein levels． Using MTT assay and AnnexinV-FITC kit to detect the stable cloned cells’ viability and apoptosis level． Results NIH3T3 cells transfected with recombinant plasmid pcDNA3. 1 /myc-His-DJ-1 or pcDNA3. 1 /myc-His-DJ-1 ^M26I screened by G418． We obtained 1 and 3 positive clones of pcDNA3. 1 /myc-His-DJ-1 and pcDNA3. 1 /myc-His-DJ-1 ^M26I transfected cells by PCR detected． The Results of RT -PCR and western blot also showed the expression of DJ-1-His in pcDNA3. 1 /myc-His-DJ-1 and pcDNA3. 1 /myc-His-DJ-1 ^M26I transfected cells． MTT assay demonstrated the NIH3T3 positive cells transfected with DJ-1 ^M26I had the lower proliferation rate than normal NIH3T3 cells( p＜0. 05) ． NIH3T3 positive cells carrying the DJ-1 genes showed no significant difference compared with the normal cells NIH3T3 cells． Apoptosis test indicated that the apoptosis rate of DJ-1 ^M26I transfected cells was higher than normal NIH3T3 cells，however the apoptosis rate of the DJ-1 transfected cells was lower than normal NIH3T3 cells( p＜0. 05) ． Conclusions Recombinant expression vectors pcDNA3. 1 /myc-His-DJ-1 and pcDNA3. 1 /mycHis-DJ-1 ^M26I have constructed successfully． The NIH3T3 cells with stable expression of DJ-1 and DJ-1 ^M26I have been constructed successfully． DJ-1 ^M26I mutation can result in the apoptosis of NIH3T3 cells easily ．