Tris-(2, 2'-bipyridyl)ruthenium(II) complex, Ru(bpy) 3 2+ , was immobilized on the Dowex-50 W cationic ion-exchange resin. The chemiluminescent characteristics of Ru(bpy) 3 2+ in solution and in resin form were compared by using batch and flow injection methods. A strong chemiluminescence was observed during the reaction of Ru(bpy) 3 2+ both in solution and in resin with KMnO 4 or Ce(SO 4 ) 2 under acidic or basic conditions. The Ru(bpy) 3 2+ immobilized resin is stable, which can be used at least for 6 months when it reacts with the dilute KMnO 4 solution. Based on this property, Ru(bpy) 3 2+ immobilized in the resin phase was developed as a flow-through chemiluminescent sensor that could be used to determine oxalate, sulfite and ethanol chemically or electronically with Ru(bpy) 3 3+ generation on the surface of resin. The limits of detection were 1×10 -6 M for oxalate, 0.5% (v/v) for ethanol and 1×10 -7 M for sulfite. The method has been successfully applied to determine sulfite in sugar.