PURPOSE: To provide a structure which can stabilize its locking for a long time regardless of external factors by applying screws in reverse rotation to a bolt and a nut. And to make it easy to release its locking, and concurrently make it possible to reuse the structure repeatedly.

CONSTITUTION: This invention is concerned with a locking structure for an object, which is so constituted that the locking of the object can be made stable by the use of an uncoupling prevention bolt after a bolt hole 3 in reverse rotation formed at the tip end section of a bolt 1 has been screwed in a nut 2.