Among various ECL systems,such as 9,10-diphenylanthraeene,lucigenin,tris(2,2'-bipyridyl) ruthenium,peroxyoxalate,luminol,graphene,and nanocrystals,Ru(bpy)_3~(2+) ECL is one of the most widely studied ECL systems in recent years due to its broad applications in immunoassays,DNA probe assays,core-actants analysis,and aptasensors. In this review,the progress in Ru(bpy)_3~(2+) ECL has been summarized on the whole,and the future research trends have been proposed.