A method of manufacturing a resin molded electronic component using a first mold having a cavity with an open top surface and a second mold combined with the first mold on top includes the following steps: (A) inserting a element of the electronic component and a liquid resin precursor into the cavity of the first mold, the liquid resin precursor having viscosity of 10 Pa·s or lower at 40° C.; (B) arranging the second mold such that the element and the resin precursor are sandwiched after the step (A); and (C) pressing the element and the resin precursor between the first mold and the second mold, and curing the resin precursor by heat from the second mold after the step (B). A temperature of the second mold is set to be higher than that of the first mold.