On the basis of LabVIEW machine vision function, using the image processing function of IMAQ Vision/Vision Assistant and the serial communication theory of virtual instrument, a set of automatic calibration device for pressure gauges which integrates image acquisition, machine vision analog reading, decision-making judgment and I/O control is designed. The test results show that the device can realize automatic reading of the pressure value displayed by the pressure gauge using a CCD camera with an error less than one tenth of the dial indexing value, which meets the measurement requirements of pressure gauge. The device achieves full automatic verification functions including fast and reliable verification of pressure gauge, automatic report generation and verification data management.