Abstract: 05Cr17Ni4Cu4Nb stainless steel valve seat is an important part of the fuel solenoid valve for aero engine, and the size of the deep hole (ϕ0.75 mm, depth 4 mm) to control the fuel flow on the valve seat is strict. Horn cemented carbide cutter for processing is small in size, poor in stiffness, and easy to vibrate during processing, resulting in unqualified processing size and low pass rate of batch products. The method of optimizing the tool angle parameters is used to reduce the cutting force, and thus the chatter of the tool. Based on DEFORM 3D simulation software, the finite element model of deep hole boring was established, and the influence of tool angle parameters on cutting force was explored by using single factor experiment method and orthogonal experiment method, and the optimal tool angle combination was selected. The results show that within the range of selected research parameters, the cutting force decreases with the increase of rake angle, clearance angle, cutting edge angle and minor cutting edge angle. The rake angle has the greatest influence on the cutting force, while the clearance angle has the smallest. The primary and secondary order of influence is the rake angle > cutting edge angle > minor cutting edge angle > clearance angle. The optimal tool angle combination is rake angle \gamma _\mathrmo =6°, clearance angle \alpha _\mathrmo =7°, cutting edge angle \kappa _\mathrmr =95°, minor cutting edge angle \kappa '_\mathrmr =5°. After optimization, the axial force is reduced by 66.90%, the radial force is reduced by 53.58%, and the tangential force is reduced by 40.69% when the tool is used to make deep holes. The maximum tool chatter deformation is reduced by 41.81%, the axial amplitude of the tool is reduced by about 44.67%, the radial amplitude by about 39.84%, and the tangential amplitude by about 41.80%. When the tool flutters, the position of the tool tip is within the allowable size range, which can effectively improve the pass rate of the product.