Some vehicle yaw dynamics modelling methods are analyzed and a new control-oriented model is proposed in the paper. These vehicle yaw dynamics models are all obtained through simplifying vehicle original physical dynamics, and they all have strong and weak points. Considering vehicle yaw stability control problem, a new observer-based vehicle yaw dynamics modelling approach for controller design is proposed, which is nonlinear and strict-feedback. And these models are further evaluated in a nonlinear vehicle simulation software, and it is testified that the proposed model is proper for yaw stability controller design.