The invention discloses a novel steel supporting base of a heavy haul railway bridge. The novel steel supporting base comprises a lower supporting base plate, a spherical slide plate, a spherical crown lining plate, a planar slide plate and an upper supporting base plate which are sequentially arranged from bottom to top, wherein the bottom surface of the upper supporting base plate is welded with a stainless steel plate and the planar slide plate to form a friction pair; the stainless steel plate and the spherical slide plate which cover the lower surface of the spherical crown lining plate form a friction pair; a sealing assembly is arranged between the side edge of the spherical crown lining plate and the lower supporting base plate; the upper supporting base plate is fixed on the bottom surface of the bridge through a bolt; and the lower supporting base plate is fixed on a pier-top pad stone by virtue of a bolt. The sealing assembly comprises a sealing skirt; and the upper edge and the lower edge of the sealing skirt are fixed on the spherical crown lining plate and the lower supporting base plate through a sealing ring and a bolt respectively. The novel steel supporting base can be suitable for the heavy haul railway bridge, can bear various loads transmitted from the heavy haul railway bridge, can safely and reliably transmit various loads to bridge piers, and can be suitable for longitudinal and transverse displacement and steering of the heavy haul railway bridge.