To prevent a pocket from being bulged with a key and prevent loss of a key and damage of clothes or bags and further, rapidly take out a key when required, by making a key portable in a state that the key is fixed to an appropriate position in a pocket of clothes or a bag.

This combination is composed of a key 1 and a keeping tool 2 for the key 1. The key 1 has a lug 11 at the basal end of a key plate 10. The keeping tool 2 for the key has a key insertion part 20 in which the key plate 10 is inserted in a state that the lug 11 is stuck out. A support part 4 supporting one side surface of the lug 11 of the key 1 and an engaging part 5 fixing the keeping tool 2 for the key to clothes or the like is provided in the key insertion part 20. A projection 44 is formed in the support 4, and a recess 15 which is attachable to the projection 44 or detachable therefrom is formed in the lug 11 of the key 1.