A device for preventing a camera from being stolen, the device comprising: a cover for covering a lens module separation button enabling a lens module to be separated from a camera body; a mounting unit for mounting the cover to the camera body; said mounting unit including a housing and a locking pin locked to a tripod locking part provided on the lower surface the camera body, a sensor provided in the mounting unit for sensing a separation of the mounting unit wherein the cover includes: a hiding part covering and hiding the lens module separation button; a covering part integrated with the hiding part and covering a lower surface of the camera body; said covering part having a through hole at a location corresponding to the tripod locking part provided on the lower surface the camera body, wherein the locking pin is locked to the tripod locking part after passing through the through hole, characterized in that the housing of the mounting unit is provided with the sensor on an inner surface thereof so that the sensor is brought into pressure contact with the covering part; and in that a longitudinal hole is provided in the housing and allowing a pin part of the locking pin to pass there through while catching a head of the locking pin. a cover for covering a lens module separation button enabling a lens module to be separated from a camera body; a mounting unit for mounting the cover to the camera body; said mounting unit including a housing and a locking pin locked to a tripod locking part provided on the lower surface the camera body, a sensor provided in the mounting unit for sensing a separation of the mounting unit wherein the cover includes: a hiding part covering and hiding the lens module separation button; a covering part integrated with the hiding part and covering a lower surface of the camera body; said covering part having a through hole at a location corresponding to the tripod locking part provided on the lower surface the camera body, wherein the locking pin is locked to the tripod locking part after passing through the through hole, characterized in that the housing of the mounting unit is provided with the sensor on an inner surface thereof so that the sensor is brought into pressure contact with the covering part; and in that a longitudinal hole is provided in the housing and allowing a pin part of the locking pin to pass there through while catching a head of the locking pin. a hiding part covering and hiding the lens module separation button; a covering part integrated with the hiding part and covering a lower surface of the camera body; said covering part having a through hole at a location corresponding to the tripod locking part provided on the lower surface the camera body, wherein the locking pin is locked to the tripod locking part after passing through the through hole, characterized in that the housing of the mounting unit is provided with the sensor on an inner surface thereof so that the sensor is brought into pressure contact with the covering part; and in that a longitudinal hole is provided in the housing and allowing a pin part of the locking pin to pass there through while catching a head of the locking pin.