This paper discusses different united brake control strategies of electric vehicle (EV), presents a novel H∞ robust united brake control strategy for EV. Research work is done under different conditions namely variable battery voltage and variable load rotational inertia, separately. A comparison between conventional PID control and H∞ robust control is done when they are applied to the above mentioned conditions. Under the united brake condition, the experimental results show that the braking distance is shortened by the united brake system in the emergent brake; the braking ability of the EV is improved. H∞ robust control has better performance than the traditional PID control both in steady-state tracking error and response speed.