NiO nanoparticles are prepared via thermal decomposition of nickel acetate coated by β-CD, and Characterized by using X-ray diffraction (XRD), transmission electron microscopy (TEM). Thermo-gravimetric (TG) analysis and electro spray mass spectrum (ESI-MS) are performed to investigate the thermal decomposition process and the possible formation mechanism of obtaining good morphology NiO nanoparticles by this method. Further, different CDs are used to prepare the precursors of inclusion complexes, and there are little affect of CD′s type on the NiO nanoparticles.