The object of this paper is to acquire the data related to insulation evaluation of hybrid vehicle traction motors. We made a comparative analysis on Insulation Resistance (IR), Dielectric Absorption Ratio (DAR), and Polarization Index (PI) of the motor stators. The experiment was carried out according to IEEE Std. 43 and IEC 60085-1 for insulation resistance test standard of rotating machinery. Test voltage of 500 V was applied between a phase and the enclosure. The IR and the DAR of used motors were lower than those of new ones. The DAR and the PI were $0.92{sim}1.02$ and $0.74{sim}1.1$, respectively and the result did not meet the recommendation basis 2 for insulation level H. From the experimental results, we could prepare parameters and basis for insulation evaluation of the traction motor stator by the comparative analysis of short-time insulation resistance changes, DAR and PI.