ZnS Nanoparticles were synthesized using PVP, PVAand PEG-4000 as capping agents by simple coprecipitation technique. The principle involved in this technique is the precipitation of metal ions with sulfide ions in the solution. 0.1 M aqueous solution of Zincacetate dihydrate and 0.1 M aqueous solution of Sodiumsulfide were mixed in the presence of various capping agent solutions like PVP, PVAand PEG-4000. First, solutions of 0.1 M Zinc acetatedihydrate, 0.1M Sodium sulfide and 1% by weight of capping agents were prepared in double distilled water. 15 ml of zinc acetate and 15 ml of 1% of PVP were mixed together and stirred for 30 minuteson a magnetic stirrer to get a homogeneous solution. This was followed by drop wise addition of appropriate amount of 0.1 M Sodium sulfide under vigorous stirring for 1 hour. A white colour precipitate was obtained which was separated by centrifugation and washed several times with double distilled water. The precipitate was dried in oven at 80oC for 4 hours to get powder sample. Using the same method, ZnS Nanoparticles were prepared using other capping agents also.