To provide an original key cover easily producable a laser beam machine so as to fit to a user's taste, and easily attachable to a key head or previously attached to the key head.

This key cover forms a receiving space where a key head of a key composed of the key head to be grasped by a user for carrying out unlocking operation and a key tail for inserting the key into a key inserting part 7 is received in the inside and fixed there, and on the other hand can lead out the key tail. The outer surface of the key cover is provided with a processing area where a desired letter or pattern is expressed by a laser beam machine or the like.