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Principally, the paper discusses some crucial aspects of a control of a demanding high frequency positioner based on piezoelectric elements. This positioner is intended for accurate driving of a mirror used in reflector of a high power laser beam. The angle of mirror deflection is spanned over ±2.5mrad, while the positioning frequency band is limited to 1000Hz. Because of the physical properties of the piezoactuator such as hysteresis, nonlinear static characteristics and temperature dependency of deflection, there was necessary to propose and apply a closed loop positioning system.  Two different positioner feedback loops are investigated and reported. The simulation experiments shown, that the most efficient controller should be able to “mask” the internal actuator hysteresis as well as to introduce appropriate dynamic stiffness to the controlled system. The theoretical considerations as well as results of model simulations and experimental investigations shown that best and most efficient controller should possess dominating proportion action, while suppressing derivative action particularly sensitive to high frequency noise. Additionally, the block schematic of the positioner controller was described and some chosen results of real experiments are attached. Finally, the assessment of the values of the control quality factors is given together with some general conclusions closing the paper.