NOVELTY - The foldable solar power collecting device comprises a supporting stem (21), a slidable housing installed on and able to slide along with the supporting stem, supporting arms, a specular member connected to the supporting stem, a light-guide pillar (3) positioned on the supporting stem, a solar cell (4) positioned on the light-guide pillar, and a transmissive protection cap (5) for covering the specular member and the light-guide pillar. A first end of the supporting arms is rotably connected to the slidable housing.    USE - Used as a foldable solar power collecting device.    ADVANTAGE - The foldable and portable solar power collecting device is capable of efficiently producing electricity without generating polluting gas such as carbon dioxide thus preventing global warming.    DETAILED DESCRIPTION - The foldable solar power collecting device comprises a supporting stem (21), a slidable housing installed on and able to slide along with the supporting stem, supporting arms, a specular member connected to the supporting stem, a light-guide pillar (3) positioned on the supporting stem, a solar cell (4) positioned on the light-guide pillar, and a transmissive protection cap (5) for covering the specular member and the light-guide pillar. A first end of the supporting arms is rotably connected to the slidable housing. The specular member is: extended and folded with a sliding of the slidable housing and corresponding movement of the supporting arms; and further connected to a second end of the supporting arms. The supporting stem includes a storage battery, and a ratable bearing. The specular member includes materials consisting of cloth, plastic, polymer and metal foil. The light-guide pillar contains scattering particles. The solar cell is formed of III-V compound solar cell, silicon solar cell, multi junction solar cell or single-junction solar cell. The light-guide pillar is made of cylinder, square column, compound parabolic concentrator, compound elliptic concentrator or compound hyperbolic concentrator.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic view of a solar power collecting device.    Parabolic concentrating unit (2)    Light-guide pillar (3)    Solar cell (4)    Transmissive protection cap (5)    Supporting stem. (21)