Newly developed or produced pressure transmitters need to conduct a comprehensive test of its technical performance indicators to ensure accurate output of the value. After a period of storage, accumulation, use, or repair of the pressure sensor, its main technical performance must be verified twice to ensure that its performance indicators meet the required standards. The impact of actual production and working environment causes its output to produce nonlinear output. Therefore, an inverse model based on the third-order nonlinear polynomial is proposed for the nonlinear calibration of the pressure transmitter and the WA network model using the improved particle swarm optimization algorithm is used for temperature compensation calibration. It performs temperature compensation calibration. The maximum absolute error of the output after nonlinear calibration is compared with the commonly used end-base translation method. The maximum absolute error is reduced from 6.0265 to 0.3086. The output accuracy after temperature compensation calibration by the improved particle swarm optimization algorithm is reduced from 0.386% to 0.091% , To achieve the high-precision output of the pressure transmitter.