The present disclosure pertains to a sensor chip and an electronic device that enable efficient use of a carrier generated by photoelectric conversion. According to the present invention, in a semiconductor substrate, at least one avalanche multiplication region where a carrier generated by photoelectric conversion is multiplied is provided in each of a plurality of pixel regions, and light with which the semiconductor substrate is irradiated is collected by on-chip lenses. A plurality of the on-chip lenses are provided for each of the pixel regions. The present technology is applicable to, for example, a rear-surface irradiation type CMOS image sensor.