A lid body is provided, and the lid body includes a main body and an opening and closing system. The opening and closing system is disposed on the main body and includes a lid member, a processing unit, an opening unit, a timing unit, a display unit and a driving unit, the lid member is movably assembled on the main body and optionally covers the opening, the timing unit is set for a preset time, when the lid member moves to the opening position and uncovers the opening, the timing unit starts to count; in the meanwhile, the display unit simultaneously shows a timing state of the timing unit; and after the timing unit counts to the preset time, the driving unit drives the lid member to move to a position where the lid member covers the opening completely.