We investigated the interaction of excited ruthenium complexes with quenchers in nanochannels of Nafion-cation-conductive membranes by using luminescence quenching measurements. The quenching rate is reflected by mobility of ions in Nafion nanochannels, which depends on the relationship between the ion size and diameter or structure of the nanochannels. The quenching of excited pyrene sulfonic acid by the quencher NO2- in anion-conductive membranes is also discussed.