Abstract: It is very difficult to welding a high carbon steel rail and a high manganese steel frog,which is still a worldwide puzzle.On the base of papers,a lot of experimental investigation has been done which dealt with the welding of high manganese steel frog (600 mm long) and high-carbon steel (600 mm long).At last such technologies as increasing the thickness of the intermediate layers of the double media,wholly covering the intermediate layers,quenching the side intermediate layers of the high manganese steel twice with water and symmetrically welding have been taken to weld rails and frog successfully.The Product Qualities Supervising and Testing Center of Railway Administration has made a bending and fatigue test,a mechanical property test on welded joint and an analysis of metallurgical structure.All the results have met or surpassed the demands of the correlative standards at home and abroad.This technology can be used directly to weld rails and frogs on-line