The investigation of N-phenyl-4-amino- and N-phenyl-4-acetamido-1,8-naphthalimides containing N-benzo-15-crown-5 ether substituent showed that the presence of ionophoric fragment as N-substituent ill naphthalimide molecule provides the design of compound possessing the properties of fluorescent receptor. The addition of metal cations does not change the position of absorption and emission bands but substantial increases the fluorescence intensity. The study of molecules included the theoretical and experimental (optical, NMR) methods, analysis of intramolecular charge (electron) transfer and fluoresence properties ill the presence and absence of metal ions.