A structure and a formation method of a micro-electro mechanical system (MEMS) device are provided. The MEMS device includes a cap substrate and a MEMS substrate bonded with the cap substrate. The MEMS substrate includes a first movable element and a second movable element. The MEMS device also includes a first enclosed space surrounded by the MEMS substrate and the cap substrate, and the first movable element is in the first enclosed space. The MEMS device further includes a second enclosed space surrounded by the MEMS substrate and the cap substrate, and the second movable element is in the second enclosed space. In addition, the MEMS device includes a pressure-changing layer in the first enclosed space.