Abstract: The present disclosure relates to a solid-state imaging device that makes it possible to suppress deterioration of phase difference information, and an electronic device. There is provided a solid-state imaging device including a pixel array unit in which a plurality of pixels is two-dimensionally arrayed. The plurality of pixels includes a phase difference pixel for phase difference detection, the pixel array unit has an array pattern in which pixel units including neighboring pixels of a same color are regularly arrayed, and the phase difference pixel is partially not added when horizontal/vertical addition is performed on a pixel signal of a predetermined pixel in a horizontal direction and a pixel signal of a predetermined pixel in a vertical direction, in reading the plurality of pixels. The present disclosure can be applied to, for example, a CMOS image sensor having a phase difference pixel.