Objective: To detect whether the ANF gene transferring into the injured carotid arterial wall is able to prevent intimal hyperplasia after carotid injury. Methods: A full-length ANF cDNA was amplified from human embryo brain by reverse transcription-polymerase chain reaction (RT-PCR). It was cloned into plasmid pcDNA3 to form the pcDNA3/ANF construct. An inflated balloon (4.0 mm) at 4-6 ATM were drawn forth and back in left common carotid for 3-4 times in 30 New Zealand white rabbits for making carotid injury model. The rabbits were divided into 3 groups according to the time interval after arterial injury: the 3 days′ group, the 8 days′ group and the 21 days′ group. There were 6 rabbits for gene transferrence, 4 rabbits for control in each group. At the same time, pcDNA3/ANF coated with Tfx-50 liposome （at a charge ratio of Tfx50 Reagent to DNA of 3∶1）was transferred into the injured artery for 45 minutes , while cell culture media 199 of the same volume was injected in the control groups. The liquid was drawn back after transfection. The existence of ANF cDNA, the expression of ANF gene products and its effect on injury carotid were tested at 3, 8 and 21 days after transfection using Southern blot, dot blot, radio-immunology assay and histological sections respectively.Results: There were the ANF mRNA expression and the ANF gene existence at the gene transferring groups after delivery of hANF cDNA with the level of mRNA expression and gene existence slightly decline in 21 days group. The number of intima cells decreased by 28%compared with control group 3 days after transfection (P < 0.05). The neointima area decreased by 52%8 days after transfection (P<0.01), and decreased by 8.6%21 days after delivery (P<0.05), with no change after delivery 30 days. PcDNA3/ANF gene transfer had no effect on media area. The content of ANF in plasma showed a tendency to rise without statistical significance. Conclusion: pcDNA3/ANF coated with liposome Tfx-50 gene transfer inhibits hyperplasia of smooth musle cell and neointimal development after carotid injury.