ABSTRACT: In this study, the authors have developed a steering Hardware-In-the-Loop Simulation (HILS) system to improve the efficiency of the steering system development. In the steering HILS system, a real-time vehicle dynamics simulation and a tie rod axial force calculation by a multibody kinematics model developed by authors are realized at the same time. The accuracy of the multibody kinematics model was evaluated by comparing the calculated tie rod axial force to those of a commercial software. Then the reproducibility of the vehicle driving condition in the steering HILS system was confirmed by comparing the tie rod axial force and the steering reaction force to those of a track test using a prototype vehicle. Finally, a functionality enhancement of the multibody kinematics model was proposed to calculate a suspension compliance steer, which is caused by a deformation of rubber bushings in the suspension system.