Through analyzing and studying the principles of PTB220 pressure sensors, the analog value adjustment of tolerance pressure sensors is achieved by means of super terminal technology, the Keithley 2000 Digital Multimeter, and the linear equation. The problem that the digital adjustment influences the analog output is resolved, so to avoid the effect of the channel errors resulted from the collectors in automatic weather stations on calibration accuracy, and thereby to ensure the accuracy of the pressure data from automatic weather stations.