In　this　paper,　Cu2ZnSnS4　(CZTS)　solar　cells　absorber　layers　and　Cu2ZnSn(SxSe1-x)　4　(CZTSSe)　with　the　S/Se　ratio　varying　between　0　and　1　were　prepared　by　an　isopropanol-based　solution　method.　The　S/Se　ratio　dependence　of　photovoltaic　properties　have　been　systematically　investigated　and　the　performance　of　the　CZTS-based　solar　cells　has　been　improved　by　the　optimization　process.　This　research　would　be　helpful　for　the　development　of　cost　effective　solution-processed　CZTSSe　thin　film　solar　cells.