The invention belongs to the field of roadbed engineering, and relates to a soft soil area reinforced gravel pile supporting EPS light embankment structure and a construction method thereof, wherein the soft soil area reinforced gravel pile supporting EPS light embankment structure comprises bidirectional reinforced gravel piles, a drainage ditch, a geotechnical cloth cushion layer, a high-strength load transmission platform, a waterproof roll, edge covering soil, EPS foam blocks and a pavement structure layer; the bidirectional reinforced gravel piles are arranged in a pile group mode, are distributed in a square mode and are longitudinally arranged in a soft soil foundation; and the geotechnical cloth cushion layer, the high-strength load transfer platform, the waterproof roll and a second high-strength load transfer platform are sequentially laid on the top of the bidirectional reinforced gravel pile from bottom to top, the EPS foam blocks are filled in a layered mode, and finally a pavement structure layer is laid. The strength of the foundation is improved, the EPS foam block is used as the embankment filler, the dead weight of the embankment and the overlying load of the foundation soil are remarkably reduced, the overall stability of the structure is remarkably enhanced through the high-strength load transfer platform, and the defects that the foundation of the embankment built on the soft soil foundation is large in settlement, poor in stability and the like can be effectively overcome.