Abstract: Computational method of range of electric vehicles is introduced. The method is based on equilibrium between energy supplied by storage batteries and power used by vehicle. Parameters of BJD6100 EV are utilized to compute range and resistance power with the help of aforementioned method. Range and power consumption at constant speed are depicted in figures. Besides, the model for evaluating the influence of the battery uniformity on the power output of the battery is established. The effect of vehicle parameters and environmental temperature on the range is analyzed. With the help of field test of BJD6100 EV electric bus, computational methods and related factors of range are verified. In the meantime, suggestions that increase range are proposed.