Disclosed herein is a sliding/folding combination type portable digital communication apparatus that includes a body; a sliding folder having a first position in which it is constrained on the body, a second position in which it has slid a predetermined distance while continuously facing the body, and a third position in which it has rotated away from the body after the sliding in such a manner that it does not face the body; and a sliding hinge module positioned between the body and the sliding folder to travel together with the sliding folder and provide a force necessary for folding/unfolding the sliding folder. The user can conveniently use a single communication apparatus having the advantages of both sliding-type and folding-type apparatuses.