A portable and collapsible storage locker formed of rigid, interconnected panels which, when fully assembled, form a self-standing, integrally strong unit and, when collapsed, fold together to occupy a minimal volumetric space. Opposed side walls are hingedly connected to a front frame, and opposed end walls are hingedly connected to a rear wall panel, both to fold inwardly in interlocking fashion such that the side walls overlie the rear panel and the end walls overlie the side walls within the region bounded by the front frame. The storage locker may optionally include a full or partial height door hinged to the front frame. The door may also include a lock if desirable. The side walls include means for supporting one or more shelves for dividing the interior space of the assembled locker and the shelves may be removable or optionally hinged to a side wall panel.