portable electronic device includes a host module, a display module and a hinge structure. The hinge structure is pivotally connected to the host module and the display module. The hinge structure includes a support frame, a rotating component and two pivotal components. An end of the rotating component is installed inside the support frame and another end of the rotating component is installed inside the display module, so that the display module is capable of rotating in a first rotating direction relative to the support frame. The two pivotal components are disposed at opposite sides of the support frame and separated from the rotating component. An end of each pivotal component is installed inside the support frame and another end of each pivotal component is installed inside the host module, so that the display module is capable of rotating in a second rotating direction relative to the host module.