Silicon Carbide (SiC) and Gallium Nitride (GaN) are the Wide Bandgap (WBG) semiconductors that are becoming more popular for power electronics in the automotive industry especially in its traction inverter. This is due to their superior material characteristics and performance over traditional Silicon (Si) semiconductors, which enable higher power density and efficiency in traction inverter applications. While SiC has become more mature and widely adopted in traction inverter applications, emerging GaN technology presents the potential for superior performance. Hence, this study presented a comprehensive performance analysis on SiC and GaN-based two-level three-phase traction inverter under various operating conditions such as different switching frequency, ambient temperature, and battery voltage level. The EV powertrain system is designed in PLECS software. The finding shows that under constant RPM driving profile with 50Nm torque load, GaN-based inverter demonstrates a better performance than SiC at ambient temperature for various switching frequencies, while SiC performs better in a higher ambient temperature. Moreover, at low battery voltage, SiC shows potentially better performance. Under ECE-15 driving profile, GaN exhibits better performance that surpasses SiC, tested at room temperature and 20 kHz switching frequency. Overall, GaN holds great potential to further enhance the performance of traction inverter.