Door opening and closing device

A door opening and closing device being applied to a vehicle including:

• a vehicle body that includes a door opening;
• and a door that opens and closes the door opening, wherein,
• when a part in the door corresponding to an upper end portion of the door opening when the door is at a fully closing position of fully closing the door opening is defined as a proximal end portion of the door,
• the door opening and closing device comprises:
• a slider that moves along a roof of the vehicle body in a direction intersecting with a width direction of the door, in a state of supporting the proximal end portion of the door in such a way as to be rotatable around an axis extending in the width direction;
• and
• a main link mechanism that includes one end rotatably coupled to the vehicle body and an opposite end rotatably coupled to the door, and adjusts a posture of the door, depending on a door opening degree by changing a distance between coupling points that is a distance between a coupling point to the vehicle body and a coupling point to the door, and
• the main link mechanism decreases the distance between the coupling points as the door opening degree becomes larger.