A low-temperature storage comprising: a thermally insulated casing including an accommodating portion insulated from external air, the accommodating portion configured to accommodate an item to be refrigerated; a door provided on the thermally insulated casing, the door configured to be closed in such a manner as to be capable of opening and closing the accommodating portion; a cooling mechanism configured to cool an interior of the accommodating portion; a temperature detecting unit configured to measure a temperature in the accommodating portion; an opening and closing detecting unit configured to detect an open or a closed state of the door; and a control unit, the control unit including a temperature adjusting unit configured to control the cooling mechanism so that a temperature measured by the temperature detecting unit becomes equal to a predetermined target temperature, a first temperature storing unit configured to store a first temperature, a second temperature storing unit configured to store a second temperature higher than the first temperature, a target temperature setting unit configured to set a target temperature at the first temperature when the opening and closing detecting unit detects that the door has been changed from an open state to closed state, and thereafter set the target temperature at the second temperature, and a control information setting unit configured to set the first temperature stored in the first temperature storing unit or the second temperature stored in the second temperature storing unit by acquiring information inputted by a user, the information inputted by the user including a user designated first temperature and a user designated second temperature, characterized by the control information setting unit further configured to, when a difference between the user designated first and second temperatures is equal to or greater than a predetermined value, output information indicating that the difference between the user designated first and second temperatures is equal to or greater than the predetermined value. a thermally insulated casing including an accommodating portion insulated from external air, the accommodating portion configured to accommodate an item to be refrigerated; a door provided on the thermally insulated casing, the door configured to be closed in such a manner as to be capable of opening and closing the accommodating portion; a cooling mechanism configured to cool an interior of the accommodating portion; a temperature detecting unit configured to measure a temperature in the accommodating portion; an opening and closing detecting unit configured to detect an open or a closed state of the door; and a control unit, the control unit including a temperature adjusting unit configured to control the cooling mechanism so that a temperature measured by the temperature detecting unit becomes equal to a predetermined target temperature, a first temperature storing unit configured to store a first temperature, a second temperature storing unit configured to store a second temperature higher than the first temperature, a target temperature setting unit configured to set a target temperature at the first temperature when the opening and closing detecting unit detects that the door has been changed from an open state to closed state, and thereafter set the target temperature at the second temperature, and a control information setting unit configured to set the first temperature stored in the first temperature storing unit or the second temperature stored in the second temperature storing unit by acquiring information inputted by a user, the information inputted by the user including a user designated first temperature and a user designated second temperature, a temperature adjusting unit configured to control the cooling mechanism so that a temperature measured by the temperature detecting unit becomes equal to a predetermined target temperature, a first temperature storing unit configured to store a first temperature, a second temperature storing unit configured to store a second temperature higher than the first temperature, a target temperature setting unit configured to set a target temperature at the first temperature when the opening and closing detecting unit detects that the door has been changed from an open state to closed state, and thereafter set the target temperature at the second temperature, and a control information setting unit configured to set the first temperature stored in the first temperature storing unit or the second temperature stored in the second temperature storing unit by acquiring information inputted by a user, the information inputted by the user including a user designated first temperature and a user designated second temperature,