An apparatus for collecting a tubular box in a flattened configuration from a store, for opening-out the tubular box and for transferring the tubular box towards a receiving station of the tubular box, the tubular box in the flattened configuration comprising a first sheet and a second sheet which are in contact with one another or in close proximity to one another, the first sheet being connected to the second sheet at two common and opposite ends, the first sheet being provided with a first wall and a second wall which are separated from one another by a first fold line; the tubular box in the flattened configuration being collectable from the outlet of a store where it is inclined by a first angle (α) with respect to a horizontal plane and exhibits the first sheet facing towards the outside such that the first wall is at a greater height than the second wall; the apparatus being positionable in a vicinity of a receiving station of the tubular box and the outlet of the store; the apparatus comprising a frame; the apparatus being characterised in that it comprises: a first member operating below the outlet of the store, which first member is hinged to the frame at a first hinge axis, bears first aspirating means and can rotate such that the first aspirating means intercept the first wall of the first sheet such as to collect the tubular box from the outlet of the store and to bring it into a folding position which is set at a lower height with respect to the outlet of the store; a second member which is hinged to the frame at a second hinge axis; a third member which is hinged to the frame at a third hinge axis; a fourth member which is hinged to the second member at a fourth hinge axis and which is hinged to the third member at a fifth hinge axis; the second member, the third member, the fourth member and the frame identifying a four-bar linkage; a fifth member which is hinged to the fourth member at a sixth hinge axis and which bears second aspirating means; an abutting member for encountering the first wall of the first sheet of the tubular box, which abutting member is arranged between the first member and the receiving station and is arranged inferiorly of the tubular box when the tubular box is in the folding position; the apparatus being designed in such a way that when the tubular box is in the folding position: the second wall of the first sheet can be intercepted by the second aspirating means and the first wall and the second wall can be moved in such a way that the second wall rotates with respect to the first wall about a hinge axis that coincides with the first fold line; the first aspirating means can disengage the first wall and the tubular box can be moved by the second aspirating means up to coming to rest on the abutting member with a consequent complete opening-out of the tubular box. a first member operating below the outlet of the store, which first member is hinged to the frame at a first hinge axis, bears first aspirating means and can rotate such that the first aspirating means intercept the first wall of the first sheet such as to collect the tubular box from the outlet of the store and to bring it into a folding position which is set at a lower height with respect to the outlet of the store; a second member which is hinged to the frame at a second hinge axis; a third member which is hinged to the frame at a third hinge axis; a fourth member which is hinged to the second member at a fourth hinge axis and which is hinged to the third member at a fifth hinge axis; the second member, the third member, the fourth member and the frame identifying a four-bar linkage; a fifth member which is hinged to the fourth member at a sixth hinge axis and which bears second aspirating means; an abutting member for encountering the first wall of the first sheet of the tubular box, which abutting member is arranged between the first member and the receiving station and is arranged inferiorly of the tubular box when the tubular box is in the folding position; the apparatus being designed in such a way that when the tubular box is in the folding position: the second wall of the first sheet can be intercepted by the second aspirating means and the first wall and the second wall can be moved in such a way that the second wall rotates with respect to the first wall about a hinge axis that coincides with the first fold line; the first aspirating means can disengage the first wall and the tubular box can be moved by the second aspirating means up to coming to rest on the abutting member with a consequent complete opening-out of the tubular box.