The present invention relates to a case assembly for a mobile terminal. The case assembly according to an aspect includes a rear surface case detachably coupled to a rear surface of a terminal body to cover the rear surface of the terminal body, a rear cover coupled to a rear surface of the rear surface case to protect the rear surface of the rear surface case, and an adhesive sheet provided between the rear surface case and the rear cover to provide an adhesive force to opposite surfaces so as to couple the rear cover to the rear surface of the rear surface case, wherein adhesive parts configured to couple the rear cover and the rear surface case to each other along an edge of the rear surface case are formed in the edge of the rear surface case and an area of the rear cover, which covers the edge of the rear surface case.