a first frame;

a second frame configured to slidably move in a first direction with respect to the first frame;

a display part configured to be flexible, partially fixed on a front surface of the first frame, wound at an end portion in a first direction of the second frame, and provided over a rear surface of the second frame, wherein a front surface area is expanded or retracted in response to a movement of the second frame;

a first guide rail fixed to the first frame and provided in a second direction parallel to the front surface area of the display part and perpendicular to the first direction;

a first slider configured to move in the second direction along the first guide rail; and

a link rotatably fastened to each of the first slider and the second frame and configured to move the second frame according to a movement of the first slider,

wherein the second frame further comprises a roller provided at the end portion in the first direction to support a rear surface of the display part,

wherein the roller comprises:

a rotational part configured to rotate; and

a fixed part that does not rotate and to which the link is fastened,

wherein the link comprises:

a first pivot that is fastened on a side of the first guide rail and configured to move along the first guide rail; and

a second pivot that is fastened on the fixed part of the roller, and

the first guide rail, the first slider and the link are provided in pairs to be symmetrical with respect to a central axis parallel to the first direction of the first frame, and

a distance between a pair of first pivots is greater than a distance between a pair of second pivots.