Electrochemical　capacitive　deionization　(CDI)　is　a　promising　technology　for　distributed　and　energy-efficient　water　desalination.　The　development　of　high-performance　capacitive　electrodes　is　critical　for　enhancing　CDI　properties　and　scaling　up　its　applications.　Herein,　a　three-dimensional　graphene　porous　architecture　with　high　CDI　performance　is　successfully　constructed　by　assembling　intentionally　designed　incomplete　graphene-based　spherical　hollow　shells.　Small　graphene　oxide　(GO)　sheets　are　purposely　adopted　to　prepare　sphere　shells　by　wrapping　the　surface　of　polystyrene　sphere　templates.　Because　the　small-sized　GO　sheets　cannot　enwrap　the　spherical　templates　seamlessly,　a　unique　graphene　hollow　shell　structure　with　integrally　interconnected　feature　forms　upon　removal　of　the　templates.　Compared　to　control　samples　with　typical　isolated　pore　structure　(3DGA-C)　prepared　with　commonly　used　large-sized　GO　sheets,　such　open　and　interconnected　porous　architectures　(3DGA-OP)　greatly　increase　their　accessibility　of　specific　surface　area　and　pore　volume,　enabling　superior　electrochemical　performance.　The　optimized　CDI　capacities　of　3DGA-OP　electrodes　reach　up　to　14.4　mg·g-1　in　NaCl　aqueous　of　500　mg·L-1　at　1.2　V,　which　is　about　2　times　the　3DGA-C　ones　(6.7　mg·g-1)　and　exceeds　the　CDI　values　of　most　reported　pure　graphene　electrodes　under　the　same　experimental　conditions.　This　strategy　of　improving　the　open　interconnectivity　between　pores　illuminates　new　avenues　for　developing　high　performance　CDI　porous　electrodes　assembled　from　two-dimensional　materials.　Copyright　©　2020　American　Chemical　Society.