The invention discloses a method and a device for constructing a V2V and V2G coexistence application scene model, a method for constructing an electric vehicle comprises establishing a charge-discharge model of the electric vehicle according to the basic characteristics of the battery of the electric vehicle, according to the user 's power demand, the state of charge of the battery after chargingand the expected state of charge of the user are analyzed, fattery loss is evaluated based on switching between battery charging and discharging states, a constraint condition is established that thetotal number of electric vehicles simultaneously performing charging is greater than the total number of vehicles performing V2V according to a V2V scenario, a target function is establish according to that optimal power consumption cost of an electric vehicle charging station, the target function satisfies the electric vehicle charging-discharging model, a charging state of the battery aft charging and a state-of-charge relationship expected by a user are satisfied, the battery loss and the constraint conditions are simultaneously considered, and the device calculates an optimal solution of the model according to the determined model. The construction method and the device can provide technical support for charge and discharge management of electric vehicles parked in electric vehicle charging stations in the future and calculate and optimize the power consumption cost of the charging stations.