Abstract: The automatic tensioner is widely used in the engine's front end accessory drive (FEAD) system. It plays a predominant role to reduce the dynamic tension and the transverse vibration of the belt span adjacent to the tensioner pulley. The static performances of a tensioner are characterized by three parameters including the static stiffness, the pre-torque and the damping coefficient of the tensioner. Experimental methods for measuring the tensioner force versus the displacement are presented. Also, the data processing techniques for establishing the curve of the tensioner torque versus the angular deflection, and for evaluating the parameters of the tensioner static performances are illustrated. The experiment results provide a validation for the modeling and the simulation of the static and dynamic performances of the FEAD system. The experiment techniques presented in this paper can also applied to measure the static stiffness of similar structures.