In this work, the fabrication and improvement of a lightweight and corrosion-resistant polyurethane (PU) based polymerconcrete are studied. The aggregate in traditional polymer concrete is generally crushed stone. Due to the low bonding strengthbetween polymer matrix and crushed stone, it is easy to fall off between polymer matrix and crushed stone after long-termuse, resulting in the degradation of the performance of polymer concrete. In order to overcome the low bond strength betweencrushed stone and polymer matrix in polymer concrete, modified polyetheramine particles were used to enhance the finalmechanical parameters of PU based polymer concrete. A series of mechanical and environmental tests were carried out, andthe effects of aggregates addition ratio and type on the mechanical properties of polymer concrete were analyzed. Theexperimental results determined the influence mechanism of aggregates proportion and type on the mechanical properties ofpolymer concrete, and obtained the appropriate aggregates type and addition proportion. The current work reveals that usingmodified polyetheramine particles as aggregates of polymer concrete can significantly enhance the bond strength anddurability between polymer matrix and aggregates. The density of this polymer concrete proposed in this paper is about 1.2g/mm3; The density of traditional polymer concrete is about 1.5-1.8 g/mm3, the weight can be reduced by 25%, and there isno problem of falling off between polymer matrix and aggregate.