Machine　tools　has　become　an　indispensable　processing　tool　in　industrial　field.　Especially　the　appearance　of　multi-axis　machine　tools　has　changed　the　traditional　processing　method.　This　paper　focuses　on　the　research　of　improving　the　machine　accuracy.　Based　on　the　general　error　model　which　has　been　established　using　multi-body　theory,　it　has　given　the　precise　NC　instructions　of　multi-axis　machine　tools.　Taking　C-A　type　machine　tool　for　example,　the　precise　NC　instructions　of　circle　angular　has　been　given.　©　2011　Springer-Verlag.