The objective of this work was the obtaining of nanoparticles with potent antioxidant activity by supercritical antisolvent extraction process (SAE) using different methods of antioxidants extraction: subcritical fluid extraction (SFE), pressurized liquid extraction (PLE) and enhanced solvent extraction (ESE) with different operating conditions. The employed conditions in SAE process were 20 mg/mL of the extract concentration, 150 bar of pressure and temperatures of 35 and 50 degrees C into the vessel, extract flow rate of 5 mL/min and supercritical CO2 (scCO(2)) flow rate of 30 g CO2/min. The quantification of polyphenols of mango leaves was determined by HPLC and the antioxidant activity was measured by DPPH. Spherical nano- and microparticles with diameters in the range of 0.01-1.34 pm were obtained with much stronger antioxidant activity than the extracts (SFE, PLE, ESE). The major compound found in the extracts and the SAE precipitates was iriflophenone 3-C-beta-D-glucoside.