molecules due to chemical reactions and metabolic events in the body. Phenolic compounds work to reduce the reaction of increasing the oxidation number, and are able to reduce highly reactive free radicals, lipid peroxidation processes, and metal oxides that can be obtained from oyster mushrooms. This study aims to make an antioxidant cream preparation and measure the IC50 value by conducting an antioxidant test of the ethyl acetate fraction of oyster mushroom (Pleurotus ostreotus) cream using FRAP (ferric reducing antioxidant power) and ABTS (2.2'-azino-bis (3-3) ethylbenzothiazoline-6-sulphonic acid) methods. Oyster mushrooms go through a liquid-liquid partition process and are made into cream preparations with a concentration of 2%, 4%, and 6% formulas, then the antioxidant activity is seen. Based on the measurement results of the three cream formulas, the IC50 value using the FRAP method was 110.12 in the medium category and the IC50 value with ABTS method was 84.61 in the strong category.
 
 Keywords: antioxidants; free radicals; oyster mushroom; frap; abts.