The utility model relates to a welding corrugated support type plate air pre-heater. The welding corrugated support type plate air pre-heater comprises flat plates (1). Downwardly-turning edges formed by punching are arranged at the left side and the right side of each flat plate (1). Upwarping edges formed by punching are arranged at the front side and the rear side of each flat plate (1). Multiple uniformly-arrayed corrugated bodies (2) are fixed on each flat plate (1). The flat plates (1) are arrayed in a laminated mode. A corrugated plate combination body (4) provided with a sealing channel is formed in such a manner that the two adjacent corrugated plates (1) are oppositely arranged and two groups of edges on the left and the right or at the front and the back are welded. Flow directions of mediums in two adjacent sealing channels are orthogonal. Four corners of each flat plate (1) are secured to a framework (3) The welding corrugated support type plate air pre-heater has following beneficial effects: heat transfer of heat transferring mediums between smoke and air in an orthogonal flow direction is carried out in the sealing channels of the two adjacent flat plate combination bodies; and a flow pattern is changed and a heat transfer effect is enhanced by the corrugated bodies of the flat plates.