Metallic-doping　chalcogenide　compounds　have　attracted　significant　interest　in　application　of　photovoltaic　devices　recently.　In　this　article,　Al-doped　SnS　films　with　a　thickness　of　about　500　nm　have　been　deposited　on　glass　substrates　by　thermal　evaporation　technique.　Al-doping　concentration　(from　0　at.　%　to　15　at.%)　in　the　SnS　films　can　be　controlled　accurately　by　varying　Al　layer　thickness.　The　effects　of　Al-doping　on　the　physical　properties　of　the　films　have　been　investigated　by　X-ray　diffraction,　scanning　electron　microscopy,　ultraviolet-visible-near　infrared　spectroscopy　measurements　and　Hall　effect　measurement　system.　All　the　films　are　orthorhombic　SnS　with　preferred　(111)　crystallites　orientation,　and　they　are　of　p-type　conductivity.　With　the　increasing　of　Al-doping　concentration,　the　evaluated　direct　band　gap　E　dir　of　the　SnS:　Al　films　decreases　from　1.50eV　to　1.29eV　and　the　conductivities　of　the　films　increase.　Therefore,　the　optical　and　semiconducting　properties　of　the　SnS　films　have　been　improved　by　Al-doping.　©　(2012)　Trans　Tech　Publications,　Switzerland.