This study is an introduction to the five-axis milling using polynomial interpolation approach. Progressive milling technologies using different spline interpolations in the control system Sinumerik 840D were compared for a defined number and distributions of the controls points of a planar curve. A tool trajectory for the five-axis CNC milling of a concave profile was generated as the superposition of the third order polynomials, that had been generated with a special algorithm in Mathematica.