A solid-state imaging device including an imaging region having a plurality of pixels arranged in a two-dimensional matrix and a peripheral circuit detecting output signals from the pixels. An impurity concentration in a transistor of each pixel is lower than an impurity concentration in a transistor of the peripheral circuit. Further, the impurity concentration of a semiconductor well region under a floating diffusion portion in the pixel is set to be lower than the impurity concentration of a semiconductor well region under a transistor portion at the subsequent stage of the floating diffusion portion.