A storage container comprising: a bag member made of soft material and configured to store a toner, wherein the bag member is a polyhedral member having a mouthpiece that forms a toner discharge port, two first flat portions facing each other, two second flat portions facing each other and coupling the first flat portions and a third flat portion facing the mouthpiece, wherein a first fold is formed on each of the second flat portions and a second fold is formed on the third flat portion so that the two first flat portions can be made to touch each other in a parallel direction after the storage container is empty, wherein the first fold and the second fold, provided on the bag member, along which the bag member deforms into a predetermined shape and reduces in volume, due to any one of when external pressure is applied to the bag member, when internal pressure of the bag member reduces, and when volume of the stored toner reduces; a guide member that is flat and is a rigidity enhancing member serving as a deformation assisting unit to assist in deformation of the bag member, is provided on each of the first flat portions; and a grasp guiding unit that guides a user about a position of grasping the bag member, and that is provided on an outer peripheral surface of the bag member, characterized in that the grasp guiding unit comprises a plurality of holes which are marks and which are provided in each guide member, wherein the marks are configured to indicate the user of a position of placing a finger at the time of grasping the bag member, wherein each hole is formed at a position at which a finger of a user can touch when the user grasps the bag member, wherein the holes correspond to four fingers from the forefinger to the little finger. a bag member made of soft material and configured to store a toner, wherein the bag member is a polyhedral member having a mouthpiece that forms a toner discharge port, two first flat portions facing each other, two second flat portions facing each other and coupling the first flat portions and a third flat portion facing the mouthpiece, wherein a first fold is formed on each of the second flat portions and a second fold is formed on the third flat portion so that the two first flat portions can be made to touch each other in a parallel direction after the storage container is empty, wherein the first fold and the second fold, provided on the bag member, along which the bag member deforms into a predetermined shape and reduces in volume, due to any one of when external pressure is applied to the bag member, when internal pressure of the bag member reduces, and when volume of the stored toner reduces; a guide member that is flat and is a rigidity enhancing member serving as a deformation assisting unit to assist in deformation of the bag member, is provided on each of the first flat portions; and a grasp guiding unit that guides a user about a position of grasping the bag member, and that is provided on an outer peripheral surface of the bag member, characterized in that the grasp guiding unit comprises a plurality of holes which are marks and which are provided in each guide member, wherein the marks are configured to indicate the user of a position of placing a finger at the time of grasping the bag member, wherein each hole is formed at a position at which a finger of a user can touch when the user grasps the bag member, wherein the holes correspond to four fingers from the forefinger to the little finger.