Objective: To evaluate the influence of local delivery of tissue factor pathway inhibitor gene on intimal hyperplasia after balloon injury. Methods: Thirty-six male New Zealand white rabbits were divided into three groups, saline, adenovirus-defect and TFPI gene treated group. Balloon catheter was used to induce injury to the carotid artery of rabbits and saline, adenovirus-defect and TFPI gene were locally delivered on injury site. Fourteen days after operation, the local injury vessel was removed and harvested for pathological analysis and immunohistochemical staining. Automatic image analysis system was used to detect the changes of intimal, medium, luminal area, and the proliferation index of proliferating cell nuclear antigen(PCNA). Results: Morphological analysis showed intimal hyperplasia remarkably decrease, along with the proliferation index of PCNA significantly reduction and luminal area augment significantly in TFPI gene treated group compared with saline and adenovirus-defect group. Conclusion: Local TFPI gene transferring may reduce the expression of PCNA,and decrease the intimal hyperplasia and enlarge the luminal area in carotid artery of rabbits.