In order to solve a technical problem in the prior art that the time of multi-channel read-back calibration processing is long in the technical scheme that there is no adjustment or calibration in analog output and the analog output depends on a single-chip microcomputer processor, the invention proposes a system and method for an analog output signal read-back channel based on an FPGA, wherein the system and method can quickly achieves the calibration of the analog output signal read-back channel in real time. The system provided by the invention comprises an FPGA module, a digital-analog conversion module, and a read-back channel located between the digital-analog conversion module and the FPGA module. The FPGA module is provided with an internal offset algorithm calibration submodule according to the input of a feedback module to the FPGA module. Moreover, the FPGA module, the read-back channel and the digital-analog conversion module form closed-loop control. Therefore, the system can achieve the real-time calibration of analog parameter output, and greatly improves the read-back detection precision.