This paper adopts the FEM simulation software of ABAQUS to establish the drilling simulation models of annular workpiece unit with staggered teeth BTA drill. Taking 45鄄steel as the workpiece material, cutting the differ鄄 ent diameter annular workpiece with each cutting tooth of staggered teeth BTA drill has been simulated based on the model. The chip formation process and deformation characteristics of each cutting tooth of staggered teeth BTA drill are analyzed. The distribution laws of the three components of cutting force with the radius of annular workpiece unit are studied. The results show that the cutting force components of each cutting tooth of staggered teeth BTA drill pres鄄 ents the non鄄uniform distribution law which is increasing with the radius increases. Besides, the cutting speed and feed rate have negligible impact on the cutting force distribution.