A jig used for a connector plug, the connector plug comprising: a connector plug body to be fitted to an adapter; and a slider supported on the connector plug body so as to be movable in a detaching direction which is a direction of detaching the connector plug body from the adapter, a fitting between the adapter and the connector plug body being released when the slider is moved in the detaching direction with respect to the connector plug body, the jig comprising: an insertion portion (41, 42) which can be inserted into a slot provided on the slider in an inserting direction which is an opposite direction of the detaching direction; and an operation portion extended in the detaching direction from the insertion portion, the insertion portion is comprised of a first insertion portion and a second insertion portion which are separated from each other by a predetermined distance, characterized in that the first insertion portion has a first locking portion at an opposite side of the second insertion portion so that the first locking portion can be locked to an inner wall of the slot, the second insertion portion has a second locking portion at an opposite side of the first insertion portion so that the second locking portion can be locked to the inner wall of the slot, the slider can be moved in the detaching direction when the jig is moved in the detaching direction in a state that the first locking portion and the second locking portion are locked to the inner wall of the slot, and the state that the first locking portion and the second locking portion are locked to the inner wall of the slot can be released when a force is applied to the operation portion in an inside direction to shorten the predetermined distance. a connector plug body to be fitted to an adapter; and a slider supported on the connector plug body so as to be movable in a detaching direction which is a direction of detaching the connector plug body from the adapter, a fitting between the adapter and the connector plug body being released when the slider is moved in the detaching direction with respect to the connector plug body, the jig comprising: an insertion portion (41, 42) which can be inserted into a slot provided on the slider in an inserting direction which is an opposite direction of the detaching direction; and an operation portion extended in the detaching direction from the insertion portion, an insertion portion (41, 42) which can be inserted into a slot provided on the slider in an inserting direction which is an opposite direction of the detaching direction; and an operation portion extended in the detaching direction from the insertion portion, the insertion portion is comprised of a first insertion portion and a second insertion portion which are separated from each other by a predetermined distance, characterized in that the first insertion portion has a first locking portion at an opposite side of the second insertion portion so that the first locking portion can be locked to an inner wall of the slot, the second insertion portion has a second locking portion at an opposite side of the first insertion portion so that the second locking portion can be locked to the inner wall of the slot, the slider can be moved in the detaching direction when the jig is moved in the detaching direction in a state that the first locking portion and the second locking portion are locked to the inner wall of the slot, and the state that the first locking portion and the second locking portion are locked to the inner wall of the slot can be released when a force is applied to the operation portion in an inside direction to shorten the predetermined distance.