This paper proposed a new kind of precast hollow cross-grid floor system which is fabricated by several precast panels and post-poured concrete strips. As there is a lack of data related to the vibration serviceability of this new floor system which aim at being used in the large-span buildings, an experimental investigation was conducted. The data obtained from the experiment showed the new floor system meet existing China criteria under most pedestrian excitations. The resultsalso demonstrated thepacing rate influence the vibration performances most as the crowd effect least. Then the FEM analysis was taken to predict the peak acceleration of the new kind of floor system comparing to the experimental results using different coefficient of dynamic force.