An air door device for a refrigerator, comprising: a door frame having a ventilation opening; a door plate pivotably installed to the door frame so as to controllably adjust an opening area of the ventilation opening, wherein a guide post parallel with a pivoting axis of the door plate and extending outwards is provided at one side of the door plate; and a guide plate translatably installed to the door frame and perpendicular to the pivoting axis of the door plate, wherein the guide plate has a guide recess portion to cooperate with the guide post, and an extension direction of the guide recess portion is at a predetermined angle relative to a translation direction of the guide plate so that the guide post slides in the guide recess portion to drive the door plate to rotate when the guide plate is translated, the extension direction of the guide recess portion is parallel with a plane in which the ventilation opening is located; wherein the door frame comprise a base plate and a side edge frame, the base plate having the ventilation opening arranged in its middle portion, the side edge frame which encloses the outer edges of the base plate to define an accommodation space for accommodating the door plate, the side edge frame comprises four side edges perpendicular to the base plate respectively, the four side edges comprise a first side edge and a second side edge parallel with each other, and respectively having opposite installation holes for installing pivoting shafts of the door plate, characterized in that the guide plate is attached to the outer side of the first side edge; wherein a connecting ear-plate, which extends from the surface of the door plate and away from the ventilation opening, is disposed at a side edge of the door plate; and the guide post is fixed at an end of the connecting ear-plate away from the door plate. a door frame having a ventilation opening; a door plate pivotably installed to the door frame so as to controllably adjust an opening area of the ventilation opening, wherein a guide post parallel with a pivoting axis of the door plate and extending outwards is provided at one side of the door plate; and a guide plate translatably installed to the door frame and perpendicular to the pivoting axis of the door plate, wherein the guide plate has a guide recess portion to cooperate with the guide post, and an extension direction of the guide recess portion is at a predetermined angle relative to a translation direction of the guide plate so that the guide post slides in the guide recess portion to drive the door plate to rotate when the guide plate is translated, the extension direction of the guide recess portion is parallel with a plane in which the ventilation opening is located; wherein the door frame comprise a base plate and a side edge frame, the base plate having the ventilation opening arranged in its middle portion, the side edge frame which encloses the outer edges of the base plate to define an accommodation space for accommodating the door plate, the side edge frame comprises four side edges perpendicular to the base plate respectively, the four side edges comprise a first side edge and a second side edge parallel with each other, and respectively having opposite installation holes for installing pivoting shafts of the door plate, characterized in that the guide plate is attached to the outer side of the first side edge; wherein a connecting ear-plate, which extends from the surface of the door plate and away from the ventilation opening, is disposed at a side edge of the door plate; and the guide post is fixed at an end of the connecting ear-plate away from the door plate.