The invention provides a key structure which comprises a keycap, a fixed support and fixing elements fixedly connecting the keycap with the fixed support, wherein the fixed support comprises a frame body, a fixed portion arranged in the middle of the frame body and elastic portions connected with the frame body and the fixed portion; the keycap comprise a top cover and a bottom cover; the top cover has a junction surface and comprises a housing frame formed in the middle of the junction surface; the bottom cover is provided with a through hole corresponding to the housing frame and is fixed on the junction surface and the fixed portion; and the elastic portions are subjected to tensile deformation by pressing the keycap. The key structure has the following beneficial effects: as the elastic portions of the fixed support can provide an elastic restoring force to the keycap, elastic elements and bumps are not needed and accordingly the volume of the key structure becomes smaller so as to be beneficial to thin design of an electronic device. The invention also provides the electronic device with the key structure.