Abstract: ZnS thin films were prepared by chemical bath deposition(CBD),using mixed aqueous solutions of zinc sulfate,thiourea, hydrazine hydrate and ammonia on glass sides,the as-deposited thin films were surface homogeneous.The crystal structure of ZnS thin films obtained under different deposition time and anneal time conditions is studied by XRD and it indicates that adequate deposition time(5 h)and anneal time(1 h) is very good to grow highly crystalized ZnS thin films of sphalerite structure.Optical transparenc...