A portable communication device includes a housing including a first housing portion and a second housing portion; a flexible display accommodated in the first housing portion and the second housing portion; a first hinge plate coupled to the first housing portion; a second hinge plate coupled to the second housing portion; and a hinge coupled to the first housing portion and the second housing portion, wherein the hinge includes a first hinge structure coupled to the first hinge plate and the second hinge plate, wherein the first hinge structure includes a first gear configured to be rotated corresponding to a rotation of the first hinge plate; a second gear configured to be rotated corresponding to a rotation of the second hinge plate; and a third gear located between the first gear and the second gear and configured to link the first gear and the second gear; a second hinge structure coupled to the first hinge plate and the second hinge plate, wherein the second hinge structure includes a first member having a first rail part and a second rail part formed thereon; a second member at least partially accommodated in the first rail part and configured to rotate in a first direction relative to the first member, the second member being coupled to the first hinge plate; and a third member at least partially accommodated in the second rail part and configured to rotate in a second direction relative to the first member, the third member being coupled to the second hinge plate; and a third hinge structure coupled to the first hinge plate and the second hinge plate and located between the second hinge structure and the first hinge structure, wherein the third hinge structure includes a first plate coupling portion coupled with the first hinge plate; and a second plate coupling portion coupled with the second hinge plate, wherein the first plate coupling portion and the second plate coupling portion are engaged with each other in a state in which the housing is unfolded and are disengaged from each other in a state in which the housing is at least partially folded, wherein the first plate coupling portion includes a first wing and a second wing spaced apart from each other at a predetermined interval, and wherein at least part of the second plate coupling portion is inserted and fastened between the first wing and the second wing e state in which the housing is unfolded.