Kepel or burahol (Stelechocarpus burahol (Bl.) Hook F. & Th.) is the identity flora of the Special Region of Yogyakarta. The existence of kepel plants at this time is very difficult to find, therefore this plant belongs to the category of CD (Conservation Dependent). The difficulty of procuring kepel seedlings is an obstacle in conducting cultivation, one of the alternatives to produce quality seeds is in vitro culture. This study aims to determine the use of hydrogen peroxide (H2O2) for optimization of endosperm explant sterilization kepel. The design of this study was a Completely Randomized Design (RAL) using a single factor trial design consisting of 6 treatments namely H2O2 concentrations of 5%, 10% and 15% for 10 minutes and 15 minutes. The use of hydrogen peroxide as a sterilizing agent can minimize the replacement of contamination and the formation of explants in the endosperm kepel. The use of 10% H2O2 for 10 minutes showed the optimum results in endosperm sterilization by producing a percentage of 0% contamination, 0% browning percentage and explants percentage 100%.