The utility model belongs to the technical field of buildings. The utility model discloses a circular plane large-span honeycomb type concrete open-web sandwich plate floor system. The structure comprises an upper chord layer and a lower chord layer, the lower chord layer is connected into a plurality of regular hexagonal grids through lower chord beams, the upper chord layer comprises a pluralityof regular hexagonal grids connected through upper chord beams, and the structure further comprises regular hexagonal upper chord plates which are stacked on the regular hexagonal grids and poured into a whole with the regular hexagonal grids; the regular hexagonal grids are arranged in the mode that a central regular hexagonal grid is arranged in the center through an upper chord beam/a lower chord beam, a plurality of regular hexagonal grids are arranged between the periphery of the central regular hexagonal grid and the circular edge of the floor system in a radial mode, and the radial rule is that six regular hexagonal grids are added every time one circle is added around the central regular hexagonal grid. The regular hexagonal grid edge close to the edge of the upper chord layer/lower chord layer is intersected with the circular edge to form a support; the upper chord layer and the lower chord layer are connected through shear keys. The floor system is reasonable in overall stress, uniform in internal force distribution and relatively low in construction cost.