An electronic component embedded substrate includes a core structure including a first insulating body and core wiring layers and having a cavity and having a stopper layer disposed as a bottom surface; an electronic component disposed in the cavity and attached to the stopper layer; and a build-up structure including a second insulating body covering at least a portion each of the core structure and the electronic component and filling at least a portion of the cavity, and build-up wiring layers wherein the stopper layer has a first region in which a portion of one surface is exposed from the first insulating body and a second region in which the other portion of one surface is covered with the first insulating body, and a surface roughness of one surface of the stopper layer in the first region is greater than that of the stopper layer in the second region.