A cuff unit of the present invention includes a first wall and a second wall that face each other with an object which has a rod shape interposed therebetween, an actuator that is capable of moving the first wall and the second wall in parallel with each other in a direction in which the first wall and the second wall relatively approach each other or separate from each other, a pressing fluid bag that is provided on a surface of the first wall on a side facing the object and that receives supply of a fluid from outside to inflate and press the object, and a restraining fluid bag that is provided on a surface of the second wall on a side facing the object and that receives supply of a fluid from outside to inflate along the periphery of the object.