A MEMS inertial sensor, may include a movable sensitive element; and second substrate and a third substrate. The movable sensitive element may be formed by using a first substrate which may be formed of a monocrystalline semiconductor material. The first substrate may include a first surface and a second surface which are opposite to each other. One or more conductive layers may be formed on the first surface of the first substrate The second substrate may be coupled to a surface of the one or more conductive layer on the first substrate. The third substrate may be coupled to the second surface of the first substrate. The third substrate and the second substrate are respectively arranged on two opposite sides of the movable sensitive element.