A MEMS device includes a first substrate provided with a plurality of first electrode terminals and a second substrate composed of a crystalline substrate and provided with a plurality of second electrode terminals respectively corresponding to the first electrode terminals. The first electrode terminals and the second electrode terminals are electrically bonded one-to-one. Protrusions are formed at positions corresponding to the first electrode terminals on a mounting face of the second substrate opposing the first substrate. The second electrode terminals include the protrusions and conductive material covering the protrusions.