A sliding door structure includes a door body, a vehicle body rail, a vehicle body rail support member, a door rail, and a door rail support member. The vehicle body rail support member includes a vehicle body-side end portion coupled to the vehicle body rail and capable of moving along the vehicle body rail, and a door-side end portion coupled to the door body. The vehicle body rail support member is capable of rotating about the vehicle body-side end portion, and of rotating about the door-side end portion. The door rail support member is configured to include a door-side end portion coupled to the door rail and capable of moving along the door rail, and a vehicle body-side end portion coupled to the vehicle body. The door rail support member is capable of rotating about the door-side end portion, and of rotating about the vehicle body-side end portion.

A door driving system and a refrigerator having the door driving system according to the present invention are provided with a motor, a power transmitting device for transmitting the power generated by the motor to the hinge, and an auxiliary device for receiving the power generated by the motor and generating an auxiliary force to move a door positioned in a closing position in an opening direction, so that the torque to be applied to the hinge of the door for opening and closing the door may be reduced.