A solid-state imaging device includes a plurality of photoelectric conversion units, a floating diffusion unit that is shared by the plurality of photoelectric conversion units and converts electric charge generated in each of the plurality of photoelectric conversion units into a voltage signal, a plurality of transfer units that are respectively provided in the plurality of photoelectric conversion units and transfer the electric charge generated in the plurality of photoelectric conversion units to the floating diffusion unit, a first transistor group that is electrically connected to the floating diffusion unit and includes a gate and source/drain which are arranged with a first layout configuration, and a second transistor group that is electrically connected to the floating diffusion unit, includes a gate and source/drain arranged with a second layout configuration symmetrical to the first layout configuration, and is provided in a separate area from the first transistor group.