Abstract： Objective　To study the efficacy, safety and related characteristics of ethylcellulose microcapsules containing tubeimoside as a vascular embolization agent. Methods　The ethylcellulose microcapsules containing tubeimoside was prepared using tubeimoside from bolbostemma paniculatum of Chinese medicinal herb as the core, and ethylcellulose as the shell. Transcatheter renal arterial embolization was performed with the microcapsules in 30 New Zealand white rabbits. Results　The microcapsules were white, spherical, and smooth particles, with its size to range from 40-180 μm, and its drug content was 36%(W/W); It was divergened best in 40% meglucamine diatrizoate and suspended stably, easily injected through 3 F catheter without occlusion. All of the microcapsules ruptured in about 20 days when immersed in physiological saline at 37℃. The embolized kidneys were smaller than the normal kidneys in weight and volume after 30 days（tw=102.1, tv=38.0, P<0.001）. Serial slices of the kidneys showed that the microcapsules remained mainly at the interlobular artery and the arterial arch, which measured from 110 μm to 350 μm in diameter. The vessels maintained occlusive after 30 days without formation of collateral circulation. Conclusion　Ethylcellulose microcapsules containing tubeimoside were safe and effective with angioembolic function and slow-release. It was a potential peripheral artery embolization agent.