We　design　and　synthesize　a　novel　graphene　embedded　orient-assembled　TiO2　mesoporous　spheres　composite　(OATMS/GP)　evidenced　by　SEM,　TEM　and　optical　spectra.　Mesoporous　structure,　characteristics　of　single-crystal-like　TiO2,　mixed　phases　of　anatase　and　rutile　and　embedding　of　graphene　have　been　integrated　into　a　composite　system　to　investigate　the　structure-property　relationship　for　enhancing　photocatalytic　activity.　Three-dimensional　(3D)　open　mesoporous　TiO2　microspheres　were　well　constructed　by　the　radially　oriented　self-assembly　of　single-crystal-like　TiO2　nanowires.　The　aggregation　of　nanowires　leads　to　the　formation　of　3D　hierarchical　microsphere　including　mesopores　that　is　convenient　for　light　harvesting　and　adsorption　of　reaction　molecules.　Especially,　the　phase　ratio　of　anatase　and　rutile　in　the　composite　is　readily　tunable　by　the　change　of　reaction　agents.　The　incorporation　of　graphene　accelerates　the　electron　transfer　and　further　prolongs　the　lifetime　of　the　photoinduced　electron　hole　pairs.　This　unique　structure　makes　the　composite　ideal　be　an　efficient　photocatalyst　for　the　removal　of　pollutants.　The　OATMS/GP　composite　for　degradation　of　Nitric　Oxide　(NO)　shows　an　excellently　photocatalytic　activity　and　stability　during　photocatalytic　reaction.　The　results　presented　here　are　expected　to　make　a　contribution　to　preparing　delicately　photocatalytic　nanocomposites　toward　the　promising　applications　for　air　purification　and　solar　energy　utilization.　(C)　2016　Elsevier　B.V.　All　rights　reserved.