The invention discloses a steel arch-gate making corrugated web type structural steel as main beams. Corrugated web supporting beams are welded to backwater sides of arc-shaped face plates; webs of the corrugated web supporting beams are corrugated webs formed by combining a plurality of arc-shaped webs or a plurality of fold-line-shaped webs. According to the steel arch-gate, corrugated beams are adopted to serve as supporting beams of the gate, supporting strength and inertia moment for the arc-shaped face plates can be improved, the depths (heights) of the corrugated beams on a gate plate can be regulated according to actual stress situations, the usage amount and usage density of the supporting beams can be greatly reduced under the same strength requirement situation, and assisting effects of supporting ribs are not needed any more. Therefore, the construction amount and construction strength can be greatly reduced, and the amount of steel materials can be greatly saved.