PURPOSE: To provide a lid opening and closing apparatus capable of stably holding an opened state of a lid of a carrying box and the like for collection and delivery and of gently closing the lid when it is closed.

CONSTITUTION: A hinge mechanism 5 is provided between a box main body 3 and a lid 2, and a hinge adaptor member is interposed between the lid 2 and the hinge mechanism 5 so that the lid 2 can be slidably adjusted independently of the condition of the hinge mechanism 5 and in a stepless manner with respect to the box main body 3. A slide hook lock mechanism is imparted to the hinge adaptor member 6 so that the lid 2 becomes slidable by a fixed force or greater at an opening and closing position of the lid 2.