A sensing device including a base, a pillar, an arm, a sensing element and a driving module is provided. The base has a supporting surface suitable for supporting the object. The pillar is disposed on the supporting surface. The arm has two ends and a pivot portion between the two ends. The pivot position is pivoted to the pillar along an axis substantially parallel to the supporting surface. The sensing element is disposed on the arm and located between an end and the pivot portion. The sensing element is located between the base and the object. The driving module is disposed between the arm and the base. The driving module drives the arm to pivot relatively to the pillar along the axis, and the sensing element moves toward or away from the object as the arm is pivoted.