Manufacturing planning(MP) is one of the most important portions for process planning.Automatic generation of manufacturing setup planning for CAPP is studied in this work.The mathematic model to describe the tolerance information and datum — machining feature relationship has been formulated based on extended graphics.By means of the transformation between the feature tolerance relationship graph(FTG) and the datum machining feature relationship graph (DMG),the algorithm to automatically generate setup planning has been given based on the tolerance analysis and manufacturing resources capability model.The algorithm can identify the machining feature and datum,optimize setup groups based on the manufacturing resource capability and tolerance analysis,as well as minimize the influence of the locating error stack-up on the machining quality.Finally a case study of setup planning is presented to verify the feasibility of the methodology.