SENSOR

Provided are a sensor and electronic device that enable reductions in the sealing performance of a sealant to be minimized. The sensor 10 comprises a setting part 18 which changes settings of a main sensor unit, and an annular seal ring 60, which is disposed so as to encircle a shaft 18b of the setting part 18, and seals a gap between the shaft 18b and a housing 12. The seal ring 60 comprises a curved surface section 61 which curves outward as seen in cross section, and a pair of end sections 62a, 62b, on both sides of the curved surface section 61 in the axial direction of the seal ring 60, which have a different shape from the curved surface section 61 and extend in the axial direction of the seal ring 60.