Abstract: A self-sounding tag alarm apparatus having a tag type main body attached to a commodity and automatically operable to sound an alarm when an attempt is made to steal the commodity. The apparatus includes a coupling such as a wire, pin or the like for detachably attaching the main apparatus body to the commodity, an alarm generator mounted in the main apparatus body, a detector for detecting a signal of a particular frequency produced externally of the main apparatus body and removal of the coupling, a reset signal intake device for taking into the main apparatus body a reset signal applied externally of the main apparatus body, and an alarm control device for rendering the alarm generator operative based on a detection signal received from the detector, and rendering the alarm generator inoperative based on the reset signal received from the reset signal intake device.