ZnS　is　an　important　wide　band　gap　semiconductor　with　extensive　potential　applications.　ZnS　thin　films　were　deposited　on　quartz　glass　substrates　by　radio　frequency　(RF)　magnetron　sputtering,　and　then　were　annealed　at　200　degrees　C,　350　degrees　C　and　500　degrees　C　temperatures　in　a　vacuum　atmosphere　and　a　sulfur　atmosphere　respectively.　Effects　of　the　different　annealing　atmosphere　on　structure,　optical　constants,　Raman　properties　and　band　gap　of　the　ZnS　films　were　investigated.　XRD　data　shows　cubic　structure　for　all　the　films　with　(111)　as　the　highly　preferential　orientation,　and　shows　that　sulfur　atmosphere　is　better　to　crystalline　quality　than　vacuum.　EDS　analysis　shows　that　the　sulfur　atmosphere　can　elevate　S　atomic　percentage.　Optical　constants　were　obtained　using　ellipsometry　analysis.　Raman　spectra　also　supports　that　the　sulfur　atmosphere　is　helpful　to　crystalline　quality.　The　transmission　spectra　were　measured　and　the　band　gap　of　3.16　-　3.39eV　was　obtained　using　Tauc　formula　and　extrapolation　method.　The　band　gap　of　the　films　annealed　in　S　atmosphere　has　a　blue　shift　compared　with　that　annealed　in　vacuum　at　every　same　annealing　temperature.　It　is　demonstrated　that　ZnS　films　possessing　good　structural　and　optical　properties　can　be　obtained　by　the　RF　magnetron　sputtering　and　the　sulfur　atmosphere　annealing　route.