The slab filled with Disused Expanded Polystyrene Plastic(DEPP) has many advantages. It is able to save concretes, decrease self weight and improve its functions of heat preservation, heat insulation and sound insulation. It is possible to transform DEPP into treasures and reduce environmental pollutions. So it can be widely used. In this paper, the mechanical properties of the slab filled with DEPP is explored through the experiments. Results show that the structure of the slab filled with DEPP is reasonable and satifies the correlative codes. References to the design of the slab filled with DEPP is also offered in this paper.