Abstract: There were different defects possibly existing in the processing and installation of nuclear piping. In addition, there may be a small amount of defects such as cracks existing in the piping due to the effect of operation conditions in the nuclear power plants. The residual life of nuclear piping with planar defects needs reasonable evaluation and prediction, so as to arrange the replacement program, and to avoid a serious impact on the efficiency of the nuclear power plants. In accordance with ASME and RSE-M codes, the method of residual life evaluation for austenitic stainless steel nuclear piping with planar defects was studied by numerical comparison in stress intensity factor calculation, crack growth analysis and crack stability evaluation in this paper, and the reference experience was provided for similar work .