Nanosized metal oxide namely copper oxide has been synthesized by precipitation method and characterized by using XRD (X-ray diffraction), TEM (transmission electron microscopy) and Magnetic measurements techniques. XRD studies show that copper oxide was formed as CuO and it has monoclinic structure. Magnetic measurements showed copper oxide has one unpaired electron and is paramagnetic in nature. The particle size of the synthesized copper oxide was determined by TEM. TEM images show that the size of particles of CuO varied from 12 nm to 35 nm, which is in good agreement of the theoretically predicted size of nanomaterials. This method is convenient, easy and effective in comparison to the known methods of the synthesis of nanomaterials like thermal decomposition of precursors, co-implantation of metal and oxygen ions and ultrasonic spray pyrolysis.