Abstract: A portable storage device comprises a housing having a first opening, a first directing portion and a second opening, and a main body having a storage portion, a connecting portion corresponding to the first opening, a second directing portion corresponding to the first directing portion, and a hanging portion corresponding to the second opening. The main body is slidably located inside the housing and is slidable between a first position and a second position. When the main body is situated at the first position, the connecting portion is exposed outside the first opening, and the hanging portion is hidden in the housing. The storage device is at a status of being used. When the main body is situated at the second position, the connecting portion is hidden in the housing, and the hanging portion is exposed outside the second opening. The storage device is at a status of being housed.