Through analyzing measuring probe’s displacement mechanism of turbine technology platform, establish 4_coordinates control math model of displacement mechanism, and also according to the displacement mechanism movement and positioning requirements of turbine technology platform to research the control knot, analyzing movement and the control of position closed loop, it has already realized positioning with precision. The result indicates that using this method to position has high precision and reliability, it can insure the whole experiment to accomplish safely and correctly, and also it has applied in displacement mechanism control system of air turbine test platform successfully.