Abstract: The authors revealed the traffic signs to induce the drivers' braking operation on curves. According to the cognitive theory,a driver's cognitive model was established. A simulator experiment was employed to analyze the relationship between the drivers' first braking point and the traffic sign under different conditions. The experimental results show that when the traffic sign is set away from the curve entrance,the braking operation is directly affected by traffic signs; when it is set near to the curve entrance,then such effect will be instead by the curve outline. In addition,the results also show that this process is also influenced by the internal memory system of the driver and the external environment. The experimental results verify the effective validity of the model and the related impact. With the combination of cognitive model,it could be indicated that the driver's braking operation is induced by the traffic information which meet the demand for brake decisions.