SnS　films　were　prepared　onto　the　ITO-coated　glass　substrates　by　pulse-form　electro-deposition.　The　potential　applied　to　the　substrates　was　of　pulse-form　and　its　＂on＂　potential,　V-on　was　-0.75　V　(vs.　SCE)and　＂off＂　potential,　V-off　was　varied　in　the　range　of　-0.1-0.5　V.　The　SnS　films　deposited　at　different　V-off　values　were　characterized　by　XRD,　EDX,　SEM　and　optical　measurements.　It　shows　that　all　the　films　are　polycrystalline　orthorhombic　SnS　with　grain　sizes　of　21.54-26.93　nm　and　lattice　dimensions　of　a=0.4426-0.4431　nm,　b=　1.1124-1.1134　nm　and　c=0.3970-0.3973　nm,　though　the　V-off　has　some　influence　on　the　surface　morphology　of　the　films　and　Sn/S　ratio.　When　V-off　=　0.1-0.3　V,　the　SnS　films　have　the　best　uniformity,　density　and　adhesion,　and　the　Sn/S　ratio　is　close　to　1/1.　The　direct　band　gap　of　the　films　was　estimated　to　be　between　1.23　and　1.33　eV　with　standard　deviation　within　+/-　0.03　eV,　which　is　close　to　the　theoretical　value.　The　SnS　films　exhibit　p-type　or　n-type　conductivity　and　their　resistivity　was　measured　to　be　16.8-43.1　Omega　cm.　(c)　2006　Elsevier　B.V.　All　rights　reserved.