Cuprous oxide thin films were prepared by sol-gel method was successfully deposited onto n-Si substrate. Sol solutions were prepared by dissolving copper (II) acetate in isopropyl alcohol. Diethanolamine and glucopone were added into the sol solution to dissolve the copper (II) acetate rapidly to prevent the precipitation of blue copper (II) acetate. Crystalline phases are identified by X-ray diffraction (XRD) and the crystallite size is estimated by using Scherrer’s formula which indicates that the largest crystallite size is 41.84 nm with the lowest lattice parameter 4.25 Å. The optical band gap of the films is determined by optical absorption technique and the surface morphologies of films are analyzed by scanning electron microscopy (SEM). The SEM micrographs show that the particles agglomerate with different shapes and sizes.