A door opening and closing device of a refrigerator, comprising: a door (4, 6) of the refrigerator coupled by means of a hinge unit to a main body of the refrigerator including a storage compartment (F, R) defined therein; an opening and closing unit including a drive unit for generating rotational force by means of a motor and a door rotating mechanism for rotating the door using the rotational force of the drive unit so as to open or close the door; characterized in that the door opening and closing device further comprises: a back electromotive force measuring device for measuring a back electromotive force value generated in the motor; a power circuit connected to a power supply to supply power to the motor; a back electromotive force circuit for transmitting back electromotive force of the motor to the back electromotive force measuring device; a control switch for selectively connecting the motor to one of the back electromotive force circuit and the power circuit; and a control unit for controlling the control switch to be connected to the power circuit when the motor is activated, and controlling the control switch to be connected to the back electromotive force circuit and controlling the motor to open or close the door (4, 6) when the motor is deactivated, wherein the control unit controls the door (4, 6) to be rotated in a closing direction when a predetermined back electromotive force is input to the back electromotive force measuring device in a state in which the motor is deactivated. a door (4, 6) of the refrigerator coupled by means of a hinge unit to a main body of the refrigerator including a storage compartment (F, R) defined therein; an opening and closing unit including a drive unit for generating rotational force by means of a motor and a door rotating mechanism for rotating the door using the rotational force of the drive unit so as to open or close the door; characterized in that the door opening and closing device further comprises: a back electromotive force measuring device for measuring a back electromotive force value generated in the motor; a power circuit connected to a power supply to supply power to the motor; a back electromotive force circuit for transmitting back electromotive force of the motor to the back electromotive force measuring device; a control switch for selectively connecting the motor to one of the back electromotive force circuit and the power circuit; and a control unit for controlling the control switch to be connected to the power circuit when the motor is activated, and controlling the control switch to be connected to the back electromotive force circuit and controlling the motor to open or close the door (4, 6) when the motor is deactivated, a back electromotive force measuring device for measuring a back electromotive force value generated in the motor; a power circuit connected to a power supply to supply power to the motor; a back electromotive force circuit for transmitting back electromotive force of the motor to the back electromotive force measuring device; a control switch for selectively connecting the motor to one of the back electromotive force circuit and the power circuit; and a control unit for controlling the control switch to be connected to the power circuit when the motor is activated, and controlling the control switch to be connected to the back electromotive force circuit and controlling the motor to open or close the door (4, 6) when the motor is deactivated, wherein the control unit controls the door (4, 6) to be rotated in a closing direction when a predetermined back electromotive force is input to the back electromotive force measuring device in a state in which the motor is deactivated.