This paper proposes MIP (Mixed-Integer Programming)-based power distribution optimization method for decentralized energy network with electric vehicles (EVs). Decentralized energy network is a new grid systems toward independence from existing power grid, and renewable energy is main energy source for the decentralized energy network. EVs are expected to take an important role of future mobility and energy network. Because the latest EV usually include large battery for long cruising distance, now EVs can be regarded as “moving battery.” Proposed method utilizes both battery in house and EV's battery to minimize total purchased energy and wasted energy. This method brings an opportunity to charge the surplus energy at house to EV's battery, and the total purchased energy may be reduced. Experimental results demonstrated the interconnection between the energy network with rich connectivity and EV reduced the purchased energy by more than half.