The potential feasibility of using phytantriol-based inverted type bicontinuous cubic phase as an embolization agent and sustained release system was evaluated in this study. In the ternary phytantriol-water-ethanol system, when water content was less than 30% (w/w), the injectable isotropic solution was formed and could transform into the bicontinuous cubic phase upon contacting the dissolution/body fluids. The transformation of the isotropic solution was confirmed by polarized light microscopy (PLM), small angle X-ray scattering (SAXS), resonance Raman spectroscopy, and rheological measurements. The in vitro dissolution results showed that the release was sustained for up to 30 days and was affected by drug loading and the initial compositions of isotropic solutions. In vivo, the embolization study was performed with normal rabbits using transcatheter arterial embolization technique and was monitored under digital subtraction angiography (DSA). The angiographical results showed that the hepatic artery was successfully embolized with phytantriol cubic phase. Therefore, with the vascular embolization and sustained release characteristics, the phytantriol-based inverted type bicontinuous cubic phase could be used for arterial transcatheter chemoembolization on hepatocellular carcinoma. © 2010 Elsevier B.V.