The invention discloses a combined bridge and pier collision-proof structure and a construction method thereof. The combined bridge and pier collision-proof structure comprises a column pier, suspension arm structures and prestressed steel bars, wherein the suspension arm structures are arranged around the upper and lower ends of the column pier, the prestressed steel bars are penetratingly arranged between the suspension arm structures and are distributed around an axis of the column pier evenly, and a protecting layer surrounds a column space enclosed by the suspension arm structures to forman airtight space filled with energy absorption blocks. The combined bridge and pier collision-proof structure has the advantages that the prestressed steel bars and the energy absorption blocks arearranged around the column pier densely, and horizontal collision force of ships or vehicles during collision is borne by the prestressed steel bars and the energy absorption blocks jointly; the prestressed steel bars under collision deform transversely while tension force of steel ropes increases sharply and is converted into vertical pressure on the column pier to share part of horizontal collision force, the rest of horizontal force is borne by the energy absorption blocks, and accordingly the horizontal collision force borne by the energy absorption blocks and the column pier are reduced relatively.