PROBLEM TO BE SOLVED: To provide an opening/closing device capable of controlling the lead or delay of a driving machine with respect to a winding shaft regardless of an inclination angle of a guide pillar.SOLUTION: An opening/closing device A comprises: a winding shaft 2 for winding or delivering an opening/closing sheet 1； a guide pillar 3 disposed along the moving direction of the winding shaft 2； a driving machine 4 for rotationally driving the winding shaft 2； and a moving member 5 for moving the driving machine 4 along the guide pillar 3. The driving machine 4 includes a driving shaft 40 connected to an end part of the winding shaft 2. The moving member 5 includes: a slip roller 50 abutting on an outer peripheral surface of the guide pillar 3 formed in a cylindrical shape； and one or more driven rollers 51 abutting on an outer peripheral surface of the guide pillar 3 on the side of an antislip roller. The driving shaft 40 is inserted into the inside of the slip roller 50 and a gap a is formed between the slip roller 50 and the driving shaft 40.
