Abstract: From the angle of driver-vehicle-road (environment) system,nonlinear rules of driving safety perceptional relations with properties of curve-ramps were discussed.Through the research on mutual effects among driving safety perception,operating speed and properties of curve-ramps,the structural model of driver safety perception was set up.Based on the theory of fuzzy-neural networks,a 5-layer inference model of driver's safety perceptive reasoning model was built up,too.In this model horizontal curve radius,gradient and operating speeds were taken as system inputs and driver's subjective safety perception were taken as system outputs.The results of road tests and inferences from utilizing fuzzy-neural network's reasoning opera- tion of driver's safety perceptive model show that the relation between inputs and outputs of 5-layer inference model is accurate and effective in inferring safety perception.