In this paper, the principle of a test bench for real-time simulation of vehicular braking of 1/4 vehicle is proposed. The proposed test bench consists of a hardware system, including a motor, rollers, a torque controller, a pair of flywheels, a signal acquisition and processing system, and a control system. The wheel speed and vehicle speed are simulated by the roller speed and flywheel speed, respectively. The translational kinetic energy of 1/4 vehicle is simulated by the rotational kinetic energy of the flywheels. The signal acquisition and processing system is used to acquire and process the signals, such as speeds and torques in the test bench. A magnetic powder clutch in the test bench is controlled by the control system to achieve the purpose of simulating the vehicular braking. Based on the proposed test bench and the theory of vehicle dynamics, the simulation method of the translational kinetic energy of 1/4 vehicle is investigated. The mathematical models of the real-time simulation about road adhesion coefficient based on the magnetic powder clutch and 1/4 vehicular braking system based on test bench are established. The feasibility of the test bench is verified through the test benchbased and road-based simulation results.