According to the particularity of the rhombic bus chassis layout, two degrees of freedom (2-DOF) handling model were established based on front/rear wheel linkage steering. Based on the model, the stability factor was deduced, and the condition satisfying under steering was determined. At the same time, the vehicle handling stability was analyzed, and the effect on the handling stability caused by the vibration of vehicle parameters was analyzed. The analysis results have shown that the influence caused by the mass of the vehicle is very small on the vehicle handling stability, but the influence caused by the wheelbase and the position of center of mass is greater. The condition satisfying under steering and the influence caused by the changes of parameters on the vehicle handling stability will contribute to the overall design of the rhombic bus, and will have better reference value for engineering.