Abstract: Steel structures are often used in the reconstruction project of concrete structures.The connection between added steel girders and existing concrete structures are commonly encountered.The behavior of the connection affects the global working state of the joint and the stress status of added members.Finite element calculation and analysis were conducted in details on the connection joint in common use.The connection stiffness,deformation of steel anchoring plate,contact stress and the stress state of bonded rebar were analyzed and suggestions on application in projects were provided,which may be a important reference for similar projects.