Abstract: The motion inertia load of truck in curved road sections has significant oscillation and impact characteristics. Based on the dynamic simulation method by TruckSim and the field test of truck load, five types of standard curved road sections and load characteristic parameters were defined. The influence of the combination of curve type, radius, vehicle speed, and driving behavior on the motion inertia load is mainly studied. The research shows that the inertial load of truck in curved road sections has complex characteristics such as bifurcation, multiple motion modes, and oscillation effects, and basic characteristics such as eccentric loading, multi-directional combination of loading, and impact. Bifurcation is the most important load characteristic in curved road sections, which has complex coupling relationship with vehicle speed, curve radius and superelevation, and has critical speed effect. There are many kinds of motion modes such as lateral motion, roll motion, and yaw motion in curved road sections, and the inertial impact load is induced by the suspension spring. There are longitudinal acceleration and deceleration, braking motion, and multiple sway motion for the S-type, isotropic type, reverse type, and generalized type, and the load has oscillation effect after the curve is out. Bifurcation behavior, eccentric load, and excessive inertia impact were the main causes of premature and complex failure mode. The calculation method of load bifurcation, the value range of eccentric load, vertical and horizontal lateral impact coefficient were proposed to provide supports for pavement design and management.