Polyphenols occurring in nature are sensible to light, heat and oxygen. For this reason, it is necessary to entrap them into drug carriers, such as liposomes. In this work, the Supercritical assisted Liposome formation process (SuperLip) was used for the encapsulation of a polyphenol-rich aqueous extract from olive pomace. The effect on liposome morphology and encapsulation efficiency of different operative parameters was studied. Liposomes were produced with mean diameters smaller than 265 nm at 130 bar and down to 168 nm for 170 bar. Narrower liposome distribution curves were obtained changing the nozzle diameter for the atomization of water. Encapsulation efficiencies up to 58% were obtained, that are about six times larger than using conventional methods.