The importance of actinide based nano-structures is well known in the area of biology, nuclear medicine and nuclear industry. Pulsed laser ablation in liquid is recognized as an attractive technique for production of nano-structures of different metals and metal oxides with high purity. In this paper, were port synthesis of uranium-di-oxide nanoparticles by pulsed laser ablation in ethanol. The second harmonic emission of an electro-optically Q-switched nano-second Nd-YAG laser was used as the coherent source here. The structural and optical properties of the fabricated uranium-di-oxide nanoparticles were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), Energy dispersive analysis of X-rays(EDX) and UV–Vis–NIR spectrophotometry. The mean size of the particles was found to be dependent on the laser ablation parameters in particular with laser fluence. XRD and TEM analysis confirmed the phase of the synthesized material as pure crystalline uranium-di-oxide with face centred cubic structure. UV–Vis–NIR absorption spectra of the colloidal solution revealed high absorption in the UV regime.