A shelf system which is suitable to be positioned in an inner volume of a white appliance and comprises at least one shelf comprising at least one main shelf section and at least one movable shelf section, and having at least one flat position wherein the movable shelf section is situated next to the main shelf section such that at least an edge of the main shelf section is adjacent to at least an edge of the movable shelf section, and at least one folded position wherein the movable shelf section is situated in a lower region of the main shelf section by slidably movement of the movable shelf section so as to get close to the main shelf section in the flat position of the shelf, such that an upper surface of the movable shelf section on which an object is placed is facing a lower surface of the main shelf section; the shelf system comprising: - at least one guide member suitable to be fixed on at least one lateral wall of the said white appliance and comprising at least one body; at least one recess positioned on the body, wherein at least one side of the main shelf section is situated, and which permits upward and downward movement of the main shelf section in a vertical direction during the use of the shelf system in the said white appliance, and which receives the main shelf section when the movable shelf section moves the main shelf section upward in the folded position of the shelf; characterized by comprising at least one channel wherein at least one side of the movable shelf section is positioned in the flat position of the shelf, and at least an end of which opens into the said recess and said side of the movable shelf section is able to be slidably moved therein so as to move the movable shelf section close to or away from the main shelf section; - at least one guiding element that orients the movable shelf section during its transition between the flat position of the shelf and the folded position thereof, at least one side of which is connected with a side of the main shelf section that faces the movable shelf section in the flat position of the shelf, and having at least one curved surface, being S-shaped, which contacts the said upper surface of the movable shelf section, wherein at least one portion of its side that is in contact with the movable shelf section during the movement of the movable shelf section is curved, and at least one flat surface forming a bridge between the main shelf section and the movable shelf section and - at least one stopper element that extends, within the said body, as a protrusion projecting outward from the said channel, and which prevents the main shelf section situated in the recess from moving in the horizontal direction, in the folded position of the shelf, and uncontrolled dislocation of the same; wherein in the folded position of the shelf, the main shelf section and the movable shelf section are positioned in contact with each other. - at least one guide member suitable to be fixed on at least one lateral wall of the said white appliance and comprising at least one body; at least one recess positioned on the body, wherein at least one side of the main shelf section is situated, and which permits upward and downward movement of the main shelf section in a vertical direction during the use of the shelf system in the said white appliance, and which receives the main shelf section when the movable shelf section moves the main shelf section upward in the folded position of the shelf; characterized by comprising at least one channel wherein at least one side of the movable shelf section is positioned in the flat position of the shelf, and at least an end of which opens into the said recess and said side of the movable shelf section is able to be slidably moved therein so as to move the movable shelf section close to or away from the main shelf section; - at least one guiding element that orients the movable shelf section during its transition between the flat position of the shelf and the folded position thereof, at least one side of which is connected with a side of the main shelf section that faces the movable shelf section in the flat position of the shelf, and having at least one curved surface, being S-shaped, which contacts the said upper surface of the movable shelf section, wherein at least one portion of its side that is in contact with the movable shelf section during the movement of the movable shelf section is curved, and at least one flat surface forming a bridge between the main shelf section and the movable shelf section and - at least one stopper element that extends, within the said body, as a protrusion projecting outward from the said channel, and which prevents the main shelf section situated in the recess from moving in the horizontal direction, in the folded position of the shelf, and uncontrolled dislocation of the same;