We investigated the phase behavior of cationic tetradecyldimethylhydroxylammonium chloride (C14DMAOH.Cl) (a fixed surfactant concentration, 20 mM) in the presence of sodium 2-naphthalenesulfonate (SNphS) as a function of the molar,ratios beta (= SNphS/C14DMAOH.Cl) by turbidity, viscosity, dye solubilization, and polarizing microscopy. The C14DMAOH.Cl/SNphS system formed aggregates with a lower curvature than cetyltrimethylammonium bromide (C16TAB)/aromatic counterion systems, despite the shorter alkyl chain. Addition of SNphS into the C14DMAOH.Cl solution at 25degreesC produced precipitates of solid crystals above beta similar to 0.5, in contrast with long fibrous micelles of many other cationic micelle-aromatic counterion pairs. The crystalline solids (tetradecyldimethylhydroxylammonium naphthalenesulfonate, C14DMAOH.NphS) at 20 mM concentration were transformed into the lamellar liquid crystalline phase dispersion (lamellar droplets) above 54 degreesC. The lamellar phase was not spontaneously converted into vesicles upon dilution to 1 mM, in contrast to spontaneous vesicle formation of cetyltrimethylammonium hydroxynaphthalenecarboxylate (C16TAHNC). The stability of the lamellar droplets was rather limited in the low surfactant concentration of 1 mM. The phase separation into the lamellar liquid crystalline phase and the clear isotropic solution was observed within several hours. By gentle shaking by hand, on the other hand, the lamellar phase could be dispersed to lamellar droplets at 60 degreesC again. The fact that the C14DAMAOH.NphS prefers the planar bilayer structure (a precipitate or a lamellar liquid crystalline phase) to the curved bilayer structure (vesicles) may manifest the rigid surface of the bilayers. Compared with C16TAHNC, the rigid nature of the C14DMAOH.NphS bilayer is likely due to the proposed hydrogen bond formation between the two neighboring cationic headgroups, where their charge repulsion was now suppressed by the counterion binding. To examine effects of the hydrophobicity of the counterion on the phase behavior, similar experiments were carried out for sodium benzenesulfonate (SBzS) and Na2SO4. In the case of the SBzS, the interaction was much weaker than that of SNphS and no lamellar droplets were observed at elevated temperatures. Na2SO4 was found to be ineffective to induce a structural change of the micelle, despite consisting of divalent counterions.