Abstract: A 6-DOF rigid multi-body handling stability model of an articulated dump truck (ADT) was developed by Roberson-Wittenburg method. XAD250 yaw velocity gain curves under no-load and full-load states were calculated with the software MATLAB. From the curves it was found that the no-load ADT had larger under steer than the full-load one. Some parameters were calculated such as tire lateral stiffness, centroid position of every segment, and suspension system parameter, which influence the handling stability of an ADT.