The investigation of the emission spectra of an organic base, viz., quinoline, adsorbed on ion-exchange Y-zeolite forms has demonstrated the possibility of using a luminescence method for the identification and qualitative evaluation of the strength of the proton-donor sites in faujasite [i]. In the present work we have obtained the luminescence spectra of enaphthol, a compound which has acid properties, adsorbed on cation-substituted Y-zeolite forms (SiO2/AI203 = 4.7) at 50~ for the purpose of investigating the proton acceptor, base properties of faujasite. It was postulated that when basic sites are present in zeolites~ the formation of a naphthoxide ion in the latter owing to the transfer of a hydrogen ion from an adsorbed molecule to a proton-acceptor site in the sorbent would cause the appearance of a fluorescence band characteristic of the ion in the 370-470 nm region in the emission spectrum [2].