Abstract: Aim ：To investigate the function of tissue factor(TF) cytoplasmic domain，and study its biological functions in breast cancer migration. Methods ：Total RNA was isolated from human breast cells(MDA-MB-231) with Trizol，and the full-length TF and truncated TF genes were amplified by RT-PCR，and then inserted into pGEM-T vectors.DNA sequencing was performed before the amplified products were cloned into the eukaryotic expression vector pcDNA3.1(+).The recombinant plasmid was transiently transfected into MCF-7 cells by means of liposome and the expression levels were examined by RT-PCR and Western blotting.And the TF procoagulant activities were detected by chromogenic substrate assay after being transfected with TF full-length，TF truncated cDNA and empty vector.A transwell assay was employed to examine the over-expression of TF full-length and TF truncated on breast cancer cells migration. Results ：The amplified products were confirmed as the cDNA of TF full-length and TF truncated by DNA sequencing.Positive clones pcDNA3.1(+)-TF full-length and pcDNA3.1(+)-TF truncated were verified by endonuclease digestion.With the increased TF expression，procoagulant activity was also augmented.TF truncated had no effect on MCF-7 cells migration，but over-expression of TF full-length significantly increased MCF-7 cell migration. Conclusion ：The eukaryotic expression plasmids for TF full-length and TF truncated were constructed successfully，which provides a basis for further investigation on the role of TF and its cytoplasmic phosphorylation domain in cancers.