Zn nanoparticles were prepared by the inert-gas evaporation technique with induction heating method. As-prepared Zn particles were mixed with Na2S solution. ZnS nanoparticles were synthesized under ultrasonic radiation. They were studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV spectrophotometry, and X-rayphotoelectron spectrometry (XPS). XRD revealed that the ZnS nanoparticles prepared have azincblende structure. TEM observations showed that the ZnS nanoparticles are in aspherical form with an average diameter of 40nm. XPS results proved that, for our sample, the binding energies of Zn2p and S2p are the same as those of bulk single-crystal, but the full widths at half maximum of the XPS peaks are larger than those of bulk single-crystal.