A shutter mechanism of an automated-teller machine according to the present invention comprises a main body including a frame, a shutter slidably coupled to a front side of the frame, a first protrusion protruding inward on an inner lateral surface of the shutter, and a fixing member protruding on a side surface of the frame; an opening/closing means for opening and closing the shutter in response to an external signal; a locking unit for preventing the shutter from being opened by an external force without a separate signal; and a driving unit for simultaneously operating the opening/closing unit and the locking unit. Therefore, the present invention provides a shutter mechanism of an automated-teller machine, wherein a shutter-opening/closing operation and a shutter-locking operation can be simultaneously carried out using a single driving source, thereby simplifying its structure and also reducing its production costs, and interference that may occur while the shutter is being closed does not impose a load on the driving source, thereby preventing damage to and malfunction of the mechanism, reducing a failure rate and also maintaining a smooth operational state.