A portable electronic device, comprising: a flexible display unit (151, 251, 451, 551); an elastically-deformable supporting member (270, 370, 470, 570) disposed below the flexible display unit and configured to be deformed together with the flexible display unit; a pressing member (260, 360, 460) disposed below the supporting member (270, 370, 470, 570) and configured to change shape according to an applied current; and a controller electrically-connected to the pressing member and configured to control the current applied to the pressing member (260, 360, 460), wherein the pressing member (260, 360, 460) is configured to apply an external force to the supporting member (270, 370, 470, 570) according to a change of the shape of the pressing member (260, 360, 460), characterized in that the supporting member (270, 470) includes at least first and second supporting members (273, 473, 274, 474), and wherein the first and second supporting members (273, 473, 274, 474) overlap each other with the pressing member therebetween, wherein the pressing member includes first and second pressing members (261, 262), and wherein the first supporting member is disposed below the flexible display unit, the first pressing member is disposed below the first supporting member, the second supporting member is disposed below the first pressing member, and the second pressing member is disposed below the second supporting member, wherein the supporting member (270, 370) comprises: a metallic plate, and a plurality of slits (272, 372) disposed on one surface of the metallic plate, wherein the plurality of slits (272, 372) form repeated patterns on the one surface of the metallic plate and are through holes which penetrate the metallic plate. a flexible display unit (151, 251, 451, 551); an elastically-deformable supporting member (270, 370, 470, 570) disposed below the flexible display unit and configured to be deformed together with the flexible display unit; a pressing member (260, 360, 460) disposed below the supporting member (270, 370, 470, 570) and configured to change shape according to an applied current; and a controller electrically-connected to the pressing member and configured to control the current applied to the pressing member (260, 360, 460), wherein the pressing member (260, 360, 460) is configured to apply an external force to the supporting member (270, 370, 470, 570) according to a change of the shape of the pressing member (260, 360, 460), characterized in that the supporting member (270, 470) includes at least first and second supporting members (273, 473, 274, 474), and wherein the first and second supporting members (273, 473, 274, 474) overlap each other with the pressing member therebetween, wherein the pressing member includes first and second pressing members (261, 262), and wherein the first supporting member is disposed below the flexible display unit, the first pressing member is disposed below the first supporting member, the second supporting member is disposed below the first pressing member, and the second pressing member is disposed below the second supporting member, wherein the supporting member (270, 370) comprises: a metallic plate, and a plurality of slits (272, 372) disposed on one surface of the metallic plate, a metallic plate, and a plurality of slits (272, 372) disposed on one surface of the metallic plate, wherein the plurality of slits (272, 372) form repeated patterns on the one surface of the metallic plate and are through holes which penetrate the metallic plate.