In order to improve the safety of intelligent vehicle in sudden traffic dangerous condition, a humanoid intelligent decision-planning algorithm was designed for active braking system. The characteristics of braking deceleration of experienced drivers under sudden traffic hazard were simulated and the target current function Ii-hope of the braking motor under the condition of different maximum tire-road friction coefficient was established. According to the actual slip ratio λ and the maximum tire-road friction coefficient μ in the braking process, a real-time decision-planning was made for the optimal target current of the braking motor. Using CarSim’s vehicle model, a humanoid intelligent decision-planning algorithm of active braking system was built in Simulink. Through the joint simulation of CarSim and Simulink and compared with the hydraulic brake system that existed in CarSim, the braking performance of stationary target and moving target under different tire-road friction coefficients was analyzed. The results showed that in the sudden danger of traffic conditions, the designed humanoid intelligent decision-planning algorithm was able to control the slip ratio in the current road near optimal slip ratio, and when taking both comfort and safety into consideration, the braking ability of the active braking system was increased by 4.12%~4.38%, which effectively reduced the accident rate of intelligent vehicle under the dangerous traffic condition.