In　this　paper,　carbon　nanotubes　(CNTs)　were　added　to　activated　carbon　to　enhance　the　mesopores.　At　first,　different　amounts　of　CNTs　were　added　to　phenolic　resin　and　composite　spheres　were　synthesized　by　suspension　polymerization.　Then,　by　carbonizing　these　spheres　at　600　degrees　C　followed　by　steam　activation　at　850　degrees　C　for　more　than　90　min,　we　prepared　highly　developed　porous　CNTs/activated　carbon　composite　spheres.　The　composite　spheres　were　characterized　by　a　laser　particle　size　analyzer,　scanning　electron　microscopy,　Raman　spectrum,　and　nitrogen　adsorption-desorption　isotherms.　Results　showed　that　the　composite　spheres　had　good　sphericity　even　with　high　proportion　of　CNTs　(45　wt.%).　Analysis　also　showed　that　the　pore　size　distribution　of　the　composite　spheres　containing　CNTs　was　＂multi-peak＂,　especially　with　20-100-nm　pores.　The　improved　20-100-nm　porous　structures　in　the　composite　spheres　can　be　ascribed　to　aggregated　pores　of　CNT　bundles.　The　amount　of　vitamin　B12　adsorbed　on　the　45　wt.%　CNT　composite　spheres　was　as　high　as　32.38　mg/g.　The　spheres　could　be　used　as　adsorbents　for　middle-molecular-weight　toxins　or　large　molecules　in　hemoperfusion.