Disclosed are a solid-state imaging apparatus, a signal processing method of a solid-state imaging apparatus, and an electronic device, which are capable of correcting uneven sensitivities generated by multiple factors in a broad area and realizing the higher-precision image quality. A correction circuit 710 weight a sensitivity Pi corresponding to a pixel signal of each pixel related to correction in a pixel unit PU that is the correction target and a sensitivity Pi corresponding to a pixel signal of each pixel related to correction in at least one same color pixel unit PU and adjacent to the pixel unit PU that is the correction target by a weighting coefficient Wi. Consequently, the correction coefficient μ is calculated by dividing a sum of the weighted sensitivities by a total number n of pixels related to correction.