The circuit breaker is required to interrupt the current in order to prevent the spreading fault current. The re-ignition caused by remaining the high temperature gas in the opening of circuit breaker occurs. As this countermeasure, the external magnetic field application and blast gas to arc are used in order to decrease the arc temperature. It has been reported that the non-thermal equilibrium of arc is remarkable near the electrode and post arc. However, few reports have the analysis of separating electron and heavy particle momentums under consideration of the non-thermal equilibrium because the physical phenomena are complicated in the non-thermal equilibrium. In this paper, the electron and heavy particle velocity distribution under consideration of non-thermal equilibrium arc was analyzed. As a result, it is possible to quantify the electron and heavy particle velocity. The electron velocity distribution is dominant to the electric potential distribution. On the other hand, the heavy particle velocity distribution is dominant to the pressure gradient. Therefore, the difference between the electron and heavy particle velocity distribution was elucidated.