Abstract: In this paper, a high-precision output power transmitter module based on high-precision power detection and dynamic control algorithm is proposed to meet the requirements of precise control of transmission power in multi-functional integrated systems. In terms of hardware, the large signal and small signal are processed separately. Two groups of high-precision power detection circuits, composed of film couplers, dual detectors and dual acquisition circuits, are used to solve the problem that the linear dynamics of detector fail to satisfy the range of gain control, and a detailed analysis of the influence of the parameters of the coupler circuit on the detection accuracy is presented. In terms of software, the error ranges generated by different mean sample numbers are analyzed. A graded, high-precision output power is achieved by setting a look-up table corresponding to the detection voltage and attenuation value in the field programmable gate array (FPGA), adaptively adjusting the digital attenuator in the transmission component and dynamically adjusting the link gain. The test results show that the high-precision output power transmitter designed by this method can be accurately controlled according to different code rates, achieving a control range of output power control of more than 33 dB and a power accuracy of better than 0.3 dB.