An image capturing element includes a first substrate having a plurality of pixel blocks including at least one pixel, the plurality of pixel blocks being arranged to be aligned in a row direction and a column direction, and a second substrate having a plurality of control blocks including a conversion unit which converts a signal output from the pixel into a digital signal and a through electrode unit configured to output the signal converted into the digital signal by the conversion unit, the plurality of control blocks being arranged to be aligned in the row direction and the column direction.