Omeprazole　(OPZ)　as　a　high-efficiency　coreactant　in　the　electrochemiluminescence　(ECL)　of　Ru(bpy)(3)(2+)　on　a　bare　Pt　electrode　has　been　studied　in　this　paper.　Based　on　the　strong　enhancement　effect　of　OPZ　on　the　ECL　of　Ru(bpy)(3)(2+),　a　simple,　rapid　and　sensitive　method　for　the　determination　of　omeprazole　has　been　established.　Under　the　optimum　conditions,　the　logarithmic　ECL　enhancement　versus　the　logarithmic　concentration　of　OPZ　is　linear　over　a　wide　concentration　range　of　2.0　x　10(-7)　to　5.0　x　10(-4)　M　(r　=　0.9945),　with　a　detection　limit　of　2.0　x　10(-8)　M　(6.9　ng/mL,　S/N　=　3)　in　a　pH　=　11.5　100　mM　phosphate　buffer　solution　containing　1.0　x　10(-4)　M　Ru(bpy)(3)(2+).　To　demonstrate　its　applicability,　the　proposed　method　was　applied　in　the　determination　of　OPZ　in　capsules　and　the　recoveries　were　ranged　from　93.3%-106.7%.　These　provide　a　possibility　to　employ　the　new　ECL　method　for　OPZ　detection　in　pharmaceutical　preparations.　According　to　the　study　of　electrochemical　behavior,　ECL　behavior　and　ECL　emission　spectrum　of　Ru(bpy)(3)(2+)/OPZ　system,　a　possible　ECL　mechanism　was　proposed.　(C)　2014　Elsevier　Ltd.　All　rights　reserved.