During the pressure gauge calibration process, in-depth analysis of error sources and the formulation of effective correction strategies are the keys to improving calibration accuracy. Error sources can be mainly divided into two categories: systematic errors and random errors. Systematic errors may result from manufacturing defects of the pressure gauge itself, such as inaccurate elastic characteristics of the Bourdon tube and unreasonable clearances of the transmission mechanism. These errors will recur under the same measurement conditions and have a certain regularity. For systematic errors, they can be corrected by comparing with a high-precision standard pressure source, determining the error value and then using the correction factor method or adjusting the internal structure of the pressure gauge. Random errors are mostly caused by small fluctuations in environmental factors and accidental factors during the measurement process, such as instantaneous changes in ambient temperature and humidity and parallax when the operator reads the data. To reduce the impact of random errors, the number of calibrations can be increased, and the statistical averaging method can be used to reduce its interference with the final calibration results. At the same time, optimizing the calibration environment and improving the skill level and operational standardization of operators also help to reduce the occurrence of random errors, so that the calibrated pressure gauge can more accurately reflect the actual pressure value and meet the high-precision requirements for pressure measurement in industrial production and scientific research.