A　new　water-soluble　iridium(III)　diimine　complex　with　appended　sugar　was　synthesized　and　characterized.　The　electrochemiluminescent　behavior　of　the　new　complex　in　aqueous　buffer　was　first　studied　and　the　ECL　signal　was　found　to　be　much　higher　than　that　of　[Ru(bpy)(3)](2+)　at　a　Pt　working　electrode.　Tri-n-propylamine　(TPA)　and　antibiotics　were　determined　by　the　ECL　of　the　iridium(III)　complex　in　aqueous　buffer　at　the　Pt　electrode　and　the　method　was　found　to　show　good　sensitivity　and　reproducibility.　The　new　iridium(III)　complex　was　found　to　display　good　solubility　in　aqueous　solution　and　a　strong　ECL　signal　at　the　Pt　electrode,　which　might　open　up　the　possibility　of　its　application　in　analysis.