Advances in bioelectronics have great potential to address unsolved biomedical problems in the cardiovascular system. By using poly (L-lactide-co-epsilon-caprolactone), which encapsulates liquid metal to make flexible and biodegradable electrical circuitry, we develop an electronic blood vessel that can integrate flexible electronics with three layers of blood-vessel cells, to mimic and go beyond the natural blood vessel. It can improve the endothelialization process through electrical stimulation and can enable controlled gene delivery into specific parts of the blood vessel via electroporation. The electronic blood vessel has excellent biocompatibility in the vascular system and shows great patency 3 months post-implantation in a rabbit model. The electronic blood vessel would be an ideal platform to enable diagnostics and treatments in the cardiovascular system and can greatly empower personalized medicine by creating a direct link of the vascular tissue-machine interface.