A micro electro mechanical system (MEMS) device is provided. The MEMS device includes: a stage which operates in a vibration mode; an axle which supports the stage and allows rotation of the stage; and a capacitive sensor which detects rotation of the stage. The capacitive sensor includes: a sensing arm which extends from the stage; driving combs which extend from the sensing arm and rotated together with the stage; fixed combs which are fixedly supported for engagement with the driving combs, the fixed combs including surfaces overlapping opposite surfaces of the driving combs in accordance with the rotation of the driving combs; and a capacitance sensing portion which detects a capacitance change of the driving combs and the fixed combs. Therefore, the MEMS device performs precise scanning by structurally preventing deformation of the stage having a light reflecting surface.