Nanoparticles of Ferric Chloride doped ZnS has been synthesized by simple chemical precipitation method and characterized by XRD, UV-Vis analysis, Differential Thermal Analysis, Antibacterial activity, Electrochemical properties, Photoluminescence and Differential Scanning Calorimetry. XRD patterns of the samples reveal particle size, specific surface area and the formation of cubic structure. Optical band gap values have been obtained from UV-Vis absorption spectra and Fourier Transform Infra-Red (FTIR) spectroscopy. It has also been found that energy band gap (E g) increases with the increase in molar concentration of reactant solution. Thermal analysis measurement of the prepared sample shows that the thermal stability of pure ZnS is decreased due to increase in Ferric Chloride concentration. Undoped ZnS is more thermal stable when compared to FeCl3 doped ZnS. Keyword: Antibacterial activity, electrochemical properties, XRD, UV-Vis and FT-IR Spectrum.