Using carbon nanotubes (CNTs) as a substrate for initial Pt coating and subsequent glucose oxidase (GOD) immobilization to detect glucose was reported. The influence of both the orientation and the density of CNTs on the electronic properties and glucose detection was also investigated by cyclic voltammogram and chronoamperometry. The results show that GC electrodes with different CNTs modification exhibit properties in the order of low-density aligned CNTs>high-density aligned CNTs>random CNTs (LD-ACNTs>HD-ACNTs>RCNTs), in terms of reversibility and electron transfer rate. The glucose biosensor with Pt nanoparticles on the LD-ACNTs can further improve the sensitivity of the glucose detection to 3.8 A/mM. The GOD/Pt/LD-ACNTs/GC biosensor has excellent stability with almost 90% of its bioactivity maintained after storage at 4 C in phosphate buffer solution (PBS) for ten days.