Typical vehicle speed deceleration occurs at the highway exit due to the driving direction change. Well conducting the driver to control the velocity could enhance the vehicle maneuverability and give drivers more responsible time when running into potential dangerous conditions. The highway exit speed limit sigh (ESLS) is an effect reminder for the driver to slow down the vehicle. The ESLS visibility is significant to guarantee the driving safety. This research focuses on the Color Variable ESLS system, whose installation point is placed considering the vehicle dynamic difference, the traffic condition and the highway geometric design. With this system, the driver could receive the updated speed limit requirement in advance and without distraction produced by eyes contract change between the dashboard and the front sight. First, the mathematical model of the drivetrain and the engine brake is built for typical motor vehicles. The vehicle braking characteristics with various initiate speeds in the deceleration area are studied. And then the ESLS positions for kinds of curves are determined by taking into account the traffic flow and vehicle brake ability differences. The recommended decelerate value would be obtained by the detection of the vehicle type and show with the band color change. Furthermore, the simulated driving environment was used to evaluate the validity of the color variable ELSE system by record the vehicle motion trace, the velocity vector as well as the lane side boundary. The result shows that the planning ESLS positions could tolerate different vehicle types while the color various ESLS could effectively conduct the vehicle deceleration process which is meaningful for the design of the future speed limit sign.