The invention provides an image detecting module including a base, a carrier movably disposed on the base, an image detecting unit disposed on the carrier, a contact portion fixed to the carrier, and a fixed member fixed to the base. The fixed member has a protrusion movably contacting a recess of the contact portion. When an external force is exerted on the base and the carrier moves with respect to the base, the protrusion slides on a surface of the recess. When the external force is released, the protrusion slides to the bottom of the recess, such that the carrier is held in a predetermined position with respect to the base.