The objective of this work is to study the dynamic and harmonic response behavior of drilling spindle supported by hybrid bearing set (HBS). HBS consists of an angular contact bearing (ACB) and radial permanent magnetic bearing. Dynamic and harmonic analysis was performed in order to investigate the effect of bearing stiffness and thrust force on the natural frequency, critical speed and vibration amplitude of a drilling spindle system. In the first step, analyses were carried out for the spindle system supported by conventional ACB's considering the effective bearing span length. In the second step, the dynamic and harmonic responses were analyzed for the drilling spindle system supported by HBS by replacing conventional ACB's. The dynamic performance of spindle under ACB's and HBS is investigated systematically using Ansys rotor dynamic and harmonic response tool. This research highlights the feasibility of effective usage of HBS in drilling machine spindles with higher critical speeds and maximum amplitudes generating due to cutting forces.