Drill breakage is one of the major problems in small hole drilling with twist drills. Therefore, it is important to know the influence of drill shape on torsional strength. Because of the small diameter and complex cross section, accurate evaluation of torsional strength is very difficult. This paper presents the process for analyzing the torsional strength of a twist drill using the three-dimensional Finite Element Method (FEM). An FEM analysis is performed using a short cutting length model with constant web thickness. The analytical results are in good agreement with experimental results and the effectiveness of this analysis was proved.