In this paper, a planar monopole antenna is introduced, also we added some new Nano fillers such as Fumed Silica and Aluminum Oxide to RT Duriod5880 and RO3003 to produce new Nano composite materials, then new Nano composite materials are used as a substrate of a ultra-wideband monopole antenna. Antenna characteristics are considered to illustrate that, by using these Nano composite materials, antenna bandwidth has significantly improved. The return loss and radiation pattern plots of the simulated planar monopole antenna show good results. Another advantage of this modification is simple fabrication and narrow substrate thickness of the proposed monopole antenna. تفاصيل المقالة