A wearable electronic device according to one embodiment of the present invention comprises: a housing including a first part forming a first external surface of the wearable electronic device, and a second part forming a second external surface of the wearable electronic device; at least one electronic component, which is positioned in the inner space of the housing and emits the heat; and a plurality of support structures at least partially positioned between the first part and the second part in response to the at least one electronic component, wherein: a boundary portion between the first part and the second part is at least partially positioned along a surface boundary between the first external surface and the second external surface, and includes at least one opening; and at least one separation space among the plurality of support structures enables communication with the outside space of the housing through the at least one opening. Other various embodiments are possible.