Solid-state image pickup element and electronic apparatus

A solid-state image pickup element as a first aspect of the present disclosure includes a pixel array, and a plurality of AD conversion portions. The pixel array is partitioned into a plurality of pixel blocks each including a normal pixel and a pixel for phase difference detection. The plurality of AD conversion portions correspond to the respective plurality of pixel blocks, and AD-convert pixel signals based on a plurality of pixels included in the corresponding pixel block. In this case, the pixel for phase difference detection included in one pixel block of the plurality of pixel blocks, and the pixel for phase difference detection included in the other pixel block of the plurality of pixel blocks are arranged in positions corresponding to each other. The present disclosure, for example, can be applied to a CMOS image sensor.