Iron doped zinc sulfide (Fe:ZnS) thin films are synthesized by chemical bath deposition (CBD). Fe dopant concentrations are 0, 6, 12 and 18 at.-%. Chemical study is monitored by X-ray fluorescence (XRF) spectroscopy to determine the exact composition. According to the XRF analysis, we found stoichiometric composition for the undoped film. Nevertheless, the doped ones are zinc rich and sulfur poor. The deposited films are stabilized in their cubic structure. The crystalline quality of the elaborated layers is enhanced after Fe incorporation and the best crystallinity is obtained for the films doped 6 at.-% Fe. The morphological study reveals many modifications such as the appearance of nanowires for the sample doped 18 at.-% Fe. Optical performance is improved and the highest transmittance values are obtained for the sample doped 6 at.-% Fe. Photoluminescence (PL) intensity shows very sensitive feature with the rise of iron concentration.