Abstract: In order to meet the need of welding surface repairing of components made of steel 42Cr₂Mo, the microstructure and performance of different bead welding layers for steel 42Cr₂Mo in quenched and tempered state using bainite welding electrode were investigated with different welding currents and welding temperatures. The results showed that the welding performance of bainite welding electrode is good; the stronger the current is, the coarser the structure is; the hardness of the first layer of bead welding is higher than that of the second layer.