Nano-emulsions are a type of emulsions with droplets of very small diameter (20-500 nm). They are used in many different applications related to chemical, pharmaceutical, and cosmetic fields. Their preparation methods can be classified in two types: the dispersion or high-energy methods, in which mechanical energy is required to form them; and the condensation or low-energy methods, which make use of the phase transitions that take place during the emulsification process. In the present study, the low-energy emulsification method phase inversion composition (PIC) has been used to prepare nano-emulsions in the system W / oleylammonium chloride - oleylamine - C12E10 / hexadecane by addition of chlorhidric acid solutions in the mixtures formed by water, oleylamine, C12E10 and hexadecane. In this way, the oleylammonium formed along the emulsification path acts as the cationic surfactant. The results obtained, in terms of phase diagrams and nano-emulsion characteristics, are compared with those obtained in the system with oleate as anionic surfactant and oleic acid as a cosurfactant. This study has been done in order to extend the application range of the ionic nano-emulsions, not only in anionic systems, but also in cationic ones.