Nano metal oxides and binary composite of Ag doped and undoped CuO and SnO 2 nanoparticles have been synthesized by co-precipitation method and characterized by FT-IR, XRD, SEM, EDX and UV-Vis Spectral studies. XRD results show that the average crystalline size of metal oxides ranges from 13 to 32 nm. The presences of Sn-O bond in metal oxide have been observed from FT-IR measurements. Effect of silver nanoparticles on band gap changes for Nano crystalline SnO 2 , CuO and CuO: SnO 2 composite has been also investigated. This has been done by finding the optical band gap from the absorption edge which is determined from UV measurement. XRD results suggest that the introduction of Ag in metal oxides and composites can increase the crystallinity of metal oxides and Nano composite and the average crystalline size of nanoparticles. EDX spectrum shows the purity of Ag doped CuO: SnO 2 nanocomposite. From the UV -Vis spectrum it has been clearly observed that silver doped and undoped CuO: SnO 2 nanocomposite shows the similar band gap value of Indium Tin Oxide (ITO).