A door opening and closing device for a refrigerator comprising: a door (4, 5) coupled to a main body defining a storage compartment therein, by means of a hinge unit; a gasket disposed between the door (4, 5) and the main body to provide a hermetic seal therebetween; and an opening and closing unit for opening and closing the door (4, 5) with respect to the main body, wherein the opening and closing unit comprises: a drive unit for generating a driving force; a gasket separation mechanism for pushing the main body using rotational force transmitted from the drive unit to separate the gasket from the main body or the door (4, 5); and a door rotating mechanism for rotating the door (4, 5) using the rotational force transmitted from the drive unit, wherein the gasket separation mechanism comprises: a push pinion gear for transmitting the rotational force of the drive unit, and a push rack engaging with the push pinion gear to increase a distance between the main body and the door (4, 5); wherein the door rotating mechanism comprises a rotational pinion gear for transmitting the rotational force of the drive unit, and characterized in that the door rotating mechanism is operated after the gasket is separated from the main body or the door (4, 5) by means of the gasket separation mechanism; and in that the door rotating mechanism further comprises a rotational rack engaging with the rotational pinion gear and moving linearly; wherein the rotational rack engages with a hinge gear formed on an outer surface of the hinge unit; a synchronizer, which is rotated by the push rack so as to cause the rotational rack to engage with the rotational pinion gear. a door (4, 5) coupled to a main body defining a storage compartment therein, by means of a hinge unit; a gasket disposed between the door (4, 5) and the main body to provide a hermetic seal therebetween; and an opening and closing unit for opening and closing the door (4, 5) with respect to the main body, wherein the opening and closing unit comprises: a drive unit for generating a driving force; a gasket separation mechanism for pushing the main body using rotational force transmitted from the drive unit to separate the gasket from the main body or the door (4, 5); and a door rotating mechanism for rotating the door (4, 5) using the rotational force transmitted from the drive unit, wherein the gasket separation mechanism comprises: a push pinion gear for transmitting the rotational force of the drive unit, and a push rack engaging with the push pinion gear to increase a distance between the main body and the door (4, 5); wherein the door rotating mechanism comprises a rotational pinion gear for transmitting the rotational force of the drive unit, and characterized in that the door rotating mechanism is operated after the gasket is separated from the main body or the door (4, 5) by means of the gasket separation mechanism; a drive unit for generating a driving force; a gasket separation mechanism for pushing the main body using rotational force transmitted from the drive unit to separate the gasket from the main body or the door (4, 5); and a door rotating mechanism for rotating the door (4, 5) using the rotational force transmitted from the drive unit, wherein the gasket separation mechanism comprises: a push pinion gear for transmitting the rotational force of the drive unit, and a push rack engaging with the push pinion gear to increase a distance between the main body and the door (4, 5); a push pinion gear for transmitting the rotational force of the drive unit, and a push rack engaging with the push pinion gear to increase a distance between the main body and the door (4, 5); wherein the door rotating mechanism comprises a rotational pinion gear for transmitting the rotational force of the drive unit, and characterized in that the door rotating mechanism is operated after the gasket is separated from the main body or the door (4, 5) by means of the gasket separation mechanism; and in that the door rotating mechanism further comprises a rotational rack engaging with the rotational pinion gear and moving linearly; wherein the rotational rack engages with a hinge gear formed on an outer surface of the hinge unit; a synchronizer, which is rotated by the push rack so as to cause the rotational rack to engage with the rotational pinion gear.