A　new　axially　modified　silicon　phthalocyanine,　di　[5＇-(2＇,　3＇-O-isopropyl)-5-methyl　cytidineoxy]　silicon　phthalocyanine　(SiPcG),　was　prepared　and　characterized　by　H-1　NMR　and　HRMS.　This　compound　is　essentially　nonaggregated　in　N,　N-dimethyformamide　and　1%　cremophor　EL　aqueous　solution.　It　shows　a　Q-band　at　676　urn　and　fluorescence　emission　at　685　nm　in　DMF,　and　exhibits　a　Q-band　at　679　nm　and　fluorescence　emission　at　689　nm　in　1%　cremophor　EL　aqueous　solution.　The　SiPcG　shows　a　high　photodynamic　activity　against　human　hepatoma　cells　HepG2　with　an　IC50　value　down　to　7.8　X　10(-8)mol　.　L-1.　Fluorescence　confocal　microscopy　study　indicated　that　the　SiPcG　locates　preferentially　in　the　mitochondria　of　cells.　The　research　results　show　that　the　SiPcG　is　highly　potential　as　a　new　anti-cancer　photosensitizer.