The present disclosure relates to a solid-state image sensor and an electronic device capable of simultaneously imaging a subject image and detecting a moving object. A solid-state image sensor according to an aspect of the present disclosure is provided with an infrared light detection unit which outputs a moving object image on the basis of infrared light out of incident light, and a visible light detection unit which outputs a subject image on the basis of visible light out of the incident light, in which the infrared light detection unit and the visible light detection unit are stacked and simultaneously output the moving object image and the subject image with the same frame and the same angle of view. The present disclosure is applicable to, for example, an electronic device having an imaging function for detecting a moving object.