TiO2　spherical　shells　with　both　inner　and　outer　surface　modified　by　graphene　have　been　successfully　constructed　through　a　stepwise　loading　method.　This　double-sided　modification　method　greatly　increases　the　contact　area　of　the　shell　with　graphene　sheets,　which　is　beneficial　for　graphene　to　separate　more　photoelectrons　from　both　the　inner　and　outer　sides　of　the　shell　simultaneously.　The　results　of　photocatalytic　reduction　of　CO2　into　CO　indicate　that　the　modification　effects　of　inner　and　outer　wall　of　TiO2　shell　by　graphene　seem　to　be　relatively　independent　to　each　other.　As　a　result,　compared　with　the　traditional　single-sided　modified　samples,　even　these　optimal　ones,　the　loading　of　graphene　on　the　other　side　of　TiO2　shell　can　still　improve　the　photocatalytic　reduction　performance.　Moreover,　the　optimal　dosage　of　graphene　on　one　side　of　shell　surface　is　always　maintained,　without　being　affected　by　the　graphene　usage　on　the　other　side.　This　work　indicates　that　the　unique　heterojunction　obtained　by　graphene　double-sided　modification　is　advantageous　to　enhance　the　photocatalytic　CO2　reduction　performance　and　expected　to　be　extended　to　the　construction　of　other　photocatalysts.　©　2020