Dry eye disease is an ocular surface disease common in present times, more expressed in certain populations, such as senior citizens, women, people exposed to low humidity, patients with autoimmune diseases as well as younger people due to excessive everyday use of digital devices. Cationic nanoemulsions of mucoadhesive properties interact with mucins on the ocular surface and are intended for treatment of ocular surface diseases due to longer retention time of the drug and consequently its greater bioavailability. In treating symptoms of mild form of dry eye disease, cationic nanoemulsions composed of components similar to those found as constituents of the ocular surface show good results. Formulations prepared for purposes of this diploma thesis are composed of 2.5% (w/w) semisynthetic mixture of middle chain fatty acids, 0.05% (w/w) lecithin, 0.25% (w/w) macrogolglycerol ricinoleate 35, 0.05% (w/w) chitosan – semisynthetic cationic polymer with mucoadhesive properties, 2.5% (w/w) glycerol – neutrally charged alcohol suitable for nanoemulsion isotonisation and purified water to 100% (w/w). Formulations were tested for their physicochemical properties: average size, size distribution as well as zeta-potential of droplets of inner phase of nanoemulsions. In addition, mucoadhesive properties were also tested using rheological method and by measuring droplet size, size distribution and zeta-potential of nanoemulsions after the addition of mucin. Based on all conducted tests, formulation showing the potential for further development is secondary cationic nanoemulsion with chitosan oligosaccharide formed by adding a solution of chitosan oligosaccharide to the mixture before the process of microfluidisation.