In a semiconductor device, to enable control of the occurrence of warpage of a sensor chip serving as a semiconductor element and a change in the warpage as well as prevention of limitation on an arrangement area of an external terminal and a peripheral component. There is included a semiconductor element in which one plate surface side of a semiconductor substrate is set as a light-receiving side, a substrate part having a recess, the recess being open to face a front surface side that is the light-receiving side and positioning the semiconductor element on the front surface side, and a plate shaped member positioned in the recess in a state where the plate shaped member is fixed to the substrate part, the plate shaped member fixing the semiconductor element to one plate surface side and being provided via a gap on at least another plate surface side with respect to a surface forming the recess.