A suitcase including: a suitcase main body with an upper side and a lower side, wherein a concaved cavity is provided in at least one of the upper side and the lower side, a bottom wall of the concaved cavity is provided with at least one assembly hole, and a top end of the main body is provided with a lock, the suitcase further including a detachable portion and a bottom stopper; wherein when the detachable portion is put in place and secured within the concaved cavity, at least a part of the detachable portion is confined within an inner space defined by the front stop and the bottom stop of the bottom stopper. The detachable portion of the suitcase can be readily replaced depending upon the needs of a user, which is more convenient for use.