A laundry treating apparatus comprising: a cabinet having a detergent opening defined therein; a tub installed inside the cabinet ; a drum rotatably installed inside the tub ; and a storage unit for storing detergent therein, wherein the storage unit includes: a storage frame entered into the cabinet through the detergent opening ; a detergent reservoir seated in the storage frame and storing the detergent therein; and an auxiliary detergent container disposed adjacent to the detergent reservoir in the storage frame , and including a front wall, a side wall, and an open top face and a detergent storage space, wherein the detergent reservoir includes a casing having an open top face and storing the detergent therein, and a cap member detachably coupled to the top face of the casing , characterized in that the detergent reservoir is disposed to surround the front portion and the side portion of the auxiliary detergent container and in that the cap member includes a flange portion protruding toward the open top face of the auxiliary detergent container and extended along the front wall and the side wall of the auxiliary detergent container , and wherein a portion of the flange portion forms a gripping portion positioned on the open top face of the auxiliary detergent container . a cabinet having a detergent opening defined therein; a tub installed inside the cabinet ; a drum rotatably installed inside the tub ; and a storage unit for storing detergent therein, wherein the storage unit includes: a storage frame entered into the cabinet through the detergent opening ; a detergent reservoir seated in the storage frame and storing the detergent therein; and an auxiliary detergent container disposed adjacent to the detergent reservoir in the storage frame , and including a front wall, a side wall, and an open top face and a detergent storage space, wherein the detergent reservoir includes a casing having an open top face and storing the detergent therein, and a cap member detachably coupled to the top face of the casing , characterized in that the detergent reservoir is disposed to surround the front portion and the side portion of the auxiliary detergent container and in that the cap member includes a flange portion protruding toward the open top face of the auxiliary detergent container and extended along the front wall and the side wall of the auxiliary detergent container , and wherein a portion of the flange portion forms a gripping portion positioned on the open top face of the auxiliary detergent container . a storage frame entered into the cabinet through the detergent opening ; a detergent reservoir seated in the storage frame and storing the detergent therein; and an auxiliary detergent container disposed adjacent to the detergent reservoir in the storage frame , and including a front wall, a side wall, and an open top face and a detergent storage space, wherein the detergent reservoir includes a casing having an open top face and storing the detergent therein, and a cap member detachably coupled to the top face of the casing , characterized in that the detergent reservoir is disposed to surround the front portion and the side portion of the auxiliary detergent container and in that the cap member includes a flange portion protruding toward the open top face of the auxiliary detergent container and extended along the front wall and the side wall of the auxiliary detergent container , and wherein a portion of the flange portion forms a gripping portion positioned on the open top face of the auxiliary detergent container . <EOS>