The stress superimposing testing method of residual stress is different from the stress releasing way. A new stress field is introduced adding on the initial state. The residual stress is indentified by the strain increment differences of the material detected in the stress superimposing process. The traditional stress superimposing testing method including hardness and indentation method are reviewed. The principle and application of two new type of stress superimposing testing methods of residual stress are introduced, their disadvantages are also indicated.