Indium　doped　ZnS　(ZnS:In)　films　were　prepared　on　glass　substrate　using　thermal　evaporation　technology.　It　was　found　that　the　structural,　optical　and　electrical　properties　of　ZnS:In　films　strongly　depend　on　the　substrate　temperature　(Ts).　By　X-ray　diffraction　(XRD),　atomic　force　microscopy　(AFM),　transmittance　spectroscopy,　and　electric　performance　measurements,　the　effect　of　Ts　on　ZnS:In　film　is　studied　in　detail.　It　reveals　that　Ts　has　important　effect　on　ZnS　grain　size,　crystallinity,　lattice　disorder,　etc.,　which　further　leads　to　the　obvious　influence　on　its　optical　and　electrical　performance.　Under　the　optimized　Ts,　the　performance,　especially　the　conductivity,　achieved　in　this　work　is　far　higher　than　that　reported　for　other　n-type　ZnS　films.　©　2014　Chinese　Institute　of　Electronics.