The invention relates to a light collecting system for a high rise building ground floor and a low rise building. The light collecting system comprises a light collector, a light guide tube and a light splitting device, wherein a light guide prism in the light collector is used for receiving sunlights; and the lights are transmitted to the light splitting device in an indoor space of the building ground floor through the light guide tube. Sufficient outdoor sunlights can be effectively guided to rooms with inconvenient light collection in the low rise buildings, the ground floors of the high rise buildings, shady buildings, a plurality of buildings with larger depths and so on; and moreover, the light collecting system for the high rise building ground floor and the low rise building, provided by the invention, has the advantages of convenience in light collection and shielding, cleanness and no pollution.