Based on the emergency lane change cases extracted from the China naturalistic driving data, the driving steering behavior divides into three phases: collision avoidance, lateral movement and steering stabilization. Using the steering primitive fitting by Gaussian function, the distribution of the duration time, the relationship between steering wheel rate and deflection were analyzed in three phases.It is shown that the steering behavior essentially is composed of steering primitives during the emergency lane-change. However, the combination of the steering primitives is different according to the specific steering constraints in three phases. In the collision avoidance phase, a single steering primitive with high peak is used for the fast steering; in the lateral movement and stabilization phase, a combination of two or even more steering primitives is built to a more accurate steering.The steering primitive indicates the general characteristics of driver steering behaviors, and a linear relationship was found between the maximum steering wheel rate and the steering wheel deflection, something indicates a constant steering time for a single primitive. It is found that the driver steering behaviors follow the Reaching Behavior. This result is not restricted to emergency steering lane change, but has more general validity.