The invention relates to a moving assemble that is applicable to be arranged between a fixed and a moveable engine bodies of a portable electronic device. The moving assemble is provided with a sliding module arranged on the moveable engine body and a rotating module arranged between the sliding module and the fixed engine body. Therefore, the moveable engine body slides and turns relatively to the fixed engine body. Besides, the moving assemble is provided with an arresting mechanism. When the moveable engine body turns relatively to the fixed engine body via the rotating module, the arresting mechanism suspends the function of the sliding module, thus preventing the edge of the moveable engine body from exerting force on the fixed engine body improperly.