In　this　study,　a　chemically　modified　homo　zwitterionic　polysaccharide　(ZPS),　sulfated　chitosan,　was　used　to　examine　its　effects　on　murine　immune　response.　The　results　showed　that　homoZPS　could　markedly　promote　the　proliferation　of　both　splenic　T/B　cells　and　adhesive　cells.　In　particular,　flow　cytometry　assay　demonstrated　that　the　sulfated　chitosan　could　non-specifically　activate　CD3(+)　and　CD8(+)　T　cells　proliferation　in　vitro.　The　effectiveness　of　sulfated　chitosan　as　adjuvant　was　tested　using　bovine　serum　albumin　(BSA)　and　diphtheria　toxin　(DT)　as　antigens　and　compared　with　that　of　aluminum　hydroxide.　The　levels　of　specific　antibodies　to　BSA　and　DT　significantly　increased　after　homoZPS　vaccination.　Both　homoZPS　and　aluminum　hydroxide　adjuvants　could　protect　mice　against　the　attack　of　DT　from　edemas　of　spleen　and　tail.　The　present　findings　demonstrated　the　chemically　derived　homoZPS　could　be　a　potential　candidate　in　the　development　of　T-lymphocyte　dependent　vaccine　adjuvants.