Abstract: Objective To investigate the microstructure of different voltage electrospinning outer sheath and discuss the inhibitory effect of SRT2104 biodegradable outer sheath on intima proliferation of vein bridge. Methods Two voltage ranges of 5-8 kV and 12-15 kV were selected to construct the outer sheath of PLGA and observe the microstructure. Thirty New Zealand white rabbits were randomly divided into control group, non-drug loading vascular sheath group and SRT2104 group. Seven days after the operation, 4 subjects in each group were randomized to compare the results of ki-67 fluorescence staining. The remaining 6 subjects were measured immediately after the operation, 1 week and 8 weeks, and the rate of change was compared. The intimal thickness and the ratio of intimal media in each group were compared 8 weeks after surgery. Results Under electron microscope, the 5-8 kV spinning was rough and broken, and the 12-15 kV spinning was smooth and continuous. The rate of inner diameter change in SRT2104 group decreased significantly(all P<0.01) 1 and 8 weeks after surgery. The rate of change of SRT2104 group 8 weeks after surgery was also much lower than that of the non-drug carrier group(P<0.05). The change rate of peak blood flow in SRT2104 group 1 week after surgery did not change significantly(P<0.05), and the trend was the same 8 weeks after surgery(P<0.01 vs. control group; P<0.05 vs. non-drug carrier sheath group), the change rate of peak blood flow in the non-drug loading sheath group was lower than that in the control group(P<0.05). HE staining at 8 weeks after surgery showed that the film thickness of SRT2104 group decreased significantly(all P<0.01). Intima-media ratio was significantly smaller(P<0.01 vs. control group; P<0.05 vs. non-drug loading sheath). Compared with the control group, the non-drug carrier sheath group decreased significantly(P<0.01). Conclusion Spinning under 12-15 kV voltage has a good microstructure, and the SRT2104-loaded outer sheath can inhibit the intimal proliferation of vein Bridges.