A display device comprising a flexible display, the device comprising: a housing ; a roller disposed in the housing ; a flexible display which is lowered to the housing or lifted above the housing , and configured to be rolled around the roller when the flexible display is lowered and comprising a display panel , and a display cover disposed on a back surface of the display panel ; an upper assembly coupled to an upper portion of the flexible display , the upper assembly including a connecting bar disposed to be elongated on the upper portion of the display cover ; and a lift assembly connected to the connecting bar and comprising: a rotation mechanism including a motor and a power transmission member, and a controller which controls the rotation mechanism , a pair of arms and an arm joint connected to each of the pair or arms, the pair of arms including a first arm rotatably coupled to the connecting bar , a second arm coupled to the first arm and configured to be pivotably raised in response to an operation of the motor , so that when the motor is driven, the flexible display is unwound from the roller or wound around the roller , a sensing module connected to the second arm and configured to detect an angle of the second arm based on a rotation of the second arm , and configured to transmit a sensing value to the controller through a signal line connecting the sensing module and the controller . a housing ; a roller disposed in the housing ; a flexible display which is lowered to the housing or lifted above the housing , and configured to be rolled around the roller when the flexible display is lowered and comprising a display panel , and a display cover disposed on a back surface of the display panel ; an upper assembly coupled to an upper portion of the flexible display , the upper assembly including a connecting bar disposed to be elongated on the upper portion of the display cover ; and a lift assembly connected to the connecting bar and comprising: a rotation mechanism including a motor and a power transmission member, and a controller which controls the rotation mechanism , a pair of arms and an arm joint connected to each of the pair or arms, the pair of arms including a first arm rotatably coupled to the connecting bar , a second arm coupled to the first arm and configured to be pivotably raised in response to an operation of the motor , so that when the motor is driven, the flexible display is unwound from the roller or wound around the roller , a sensing module connected to the second arm and configured to detect an angle of the second arm based on a rotation of the second arm , and configured to transmit a sensing value to the controller through a signal line connecting the sensing module and the controller . a rotation mechanism including a motor and a power transmission member, and a controller which controls the rotation mechanism , a pair of arms and an arm joint connected to each of the pair or arms, the pair of arms including a first arm rotatably coupled to the connecting bar , a second arm coupled to the first arm and configured to be pivotably raised in response to an operation of the motor , so that when the motor is driven, the flexible display is unwound from the roller or wound around the roller , a sensing module connected to the second arm and configured to detect an angle of the second arm based on a rotation of the second arm , and configured to transmit a sensing value to the controller through a signal line connecting the sensing module and the controller . <EOS>