A solid-state imaging element of the present disclosure includes a pixel array unit in which unit pixels each including a photoelectric conversion unit are arranged two-dimensionally in a matrix, and a floating diffusion is shared between a plurality of the unit pixels, and a drive unit that drives to discard, into the floating diffusion, a part of a charge of a non-read pixel sharing the floating diffusion with a read pixel, during a reset period of the floating diffusion of the read pixel for reading the charge.