Abstract: The investigations on the structure steel's welding matching were reviewed.The over-matching welding can improve the fracture resistance of the welded joints by lowing the cracking driving force when the crack locates in the weld metal and the toughness of the weld metal is enough.While the over-matching also lead two problems with the increase of the structure steel's strength.The welding cold cracking susceptibility is raised and the toughness of welded metal decreases.In terms of the welding of the high-strength steel,the under-matching welding with lower welding cold cracking susceptibility and higher toughness is better than the over-matching welding to control the emergence of cold cracking and ensure the fracture resistance of welding joints.