Most automotive electronic components can cause electromagnetic interference, that can cause power electronic circuits to become unstable. As per electromagnetic compatibility (EMC) standards, these electronic circuits should meet the specifications which are not achieved under some conditions. In this paper, the conducted emissions (CEs) are generated due to the switching of a buck converter, which often occurs in automotive electronics. The noise source was found to be due to the presence of common mode currents which largely affects the performance of EMC. Two types of filtering techniques were analysed and designed, and the results were compared to find an effective filtering solution to mitigate the effects of CE due to a common mode noise for the frequency range from 150 kHz to 108 MHz according to the International Special Committee on Radio Interference (CISPR25) standard. The capacitive and parasitic impedance were calculated and then used in the simulation. Finally, the simulated and measured results are presented. The noise level can be minimized by as much as 50 dB, which is an efficient noise reduction value.