A data logger device is provided. The data logger device according to an example embodiment of the present invention comprises: a sensing unit mounted on one surface of a flexible printed circuit board, and including a sensor that detects at least one piece of information; a display unit that, when an abnormal state is detected on the basis of information measured via the sensing unit, irreversibly displays the abnormal state; a control unit that controls driving of the sensing unit and the display unit; a power supply unit that provides driving power to the control unit; and a cover member that prevents the outside exposure of the sensing unit, the display unit, the control unit, and the power supply unit.