Abstract: The new beam-column and concrete-filled steel tubular column-flat plate composite structure is characterized by the joint with dedicated connection device(hinged connection) between steel columns and concrete slab.The nodes bear only vertical loads while the horizontal loads are born by the shear wall and beam-column frame,and the unbalanced moment in the joint should be very small even naught to avoid the punching damage of slab when an earthquake occurs.The new structure is different from the general frame-shear wall or slab-column structure,therefore the experiment should be implemented to study the performance of the floor system.Through a model test of concrete filled steel tubular(CFST) column-flat plate structure(inter-cross with less than 3) with 1/2-scale,the mechanical performance should be studied under vertical uniform and horizontal loads.Resultsshow that the bearing capacity of the floor system with high security reserves is 2 times higher than the vertical design load;the relative displacement of the joint can achieve 2.25% of storey height that is two times more of a frame structure's story drift limit in Code for Seismic Design of Building Structure before the specimens were destroyed even in high ratio of shearing force from the weight of superstructure and punching shear capacity of slabs(gravity shear ratio,GSR>0.8).The seismic behavior exceeds ordinary flat floor slab.