A semiconductor device includes a wiring substrate including wiring layers, a semiconductor chip including electrode pads and mounted on the wiring substrate, and a first capacitor including a first electrode and a second electrode, and mounted on the wiring substrate. The wiring layers include a first wiring layer including a first terminal pad electrically connected with the first electrode of the first capacitor and a second terminal pad electrically connected with the second electrode of the first capacitor; and a second wiring layer on an inner side by one layer from the first wiring layer of the wiring substrate and including a first conductor pattern having a larger area than each of the first terminal pad and the second terminal pad. The first conductor pattern includes a first opening in a region overlapping with each of the first terminal pad and the second terminal pad in the second wiring layer.