Two types of terahertz (THz) modulators consisting of VO_2thin film,SiO_2su bstrate,and subwavelength metallic hole arrays have been designed and demonstrated.The transmission inten sities of these modulators can be actively tuned by the insulator-metal phase transition of VO_2with moderate o ptical pumping.By comparing the two types of structures,it is obvious that the VO_2film in metallic phase bene a th the metallic hole arrays can effectively undermine the localized enhancement of THz surface plasmons.By cont rolling the power of the pumping light,the enhanced modulation based on VO_2thin film is demonstrated.