An electric propulsion system of an electric vehicle according to one exemplary embodiment of the present disclosure includes a housing having an inside partitioned into a plurality of spaces, power conversion devices disposed in the partitioned spaces of the housing, respectively, a connection bar formed on one surface of the housing to electrically interconnect the power conversion devices and a battery, and adapters configured to connect the connection bar to the power conversion devices, wherein each of the adaptors comprises an inner side and an outer side, wherein the inner side of the adaptor is provided with conductor members formed to be electrically connected to electrodes of the power conversion devices when the electrodes are inserted therein, wherein the outer side of the adaptor is provided with shielding members covering the conductor members for shielding noise generated from the power conversion devices.