Abstract: In order to study the influence of different refining modes on the quality of weathering steel Q355GNH, the R refining furnace was changed into L refining furnace when the weathering steel in a steel plant was treated. The weathering steel produced by L refining furnace was analyzed by means of chemical composition analysis, mechanical property test and metallographic examination. The results show that the method of treating weathering steel from R refining furnace to L refining furnace had no effect on the performance of weathering steel, but also reduced the refining cost and balanced the logistics.