In order to address the shortcomings of low calibration accuracy and efficiency, as well as cumbersome manual operations, in the large-scale calibration of plug gauges in aviation manufacturing enterprises, a method for measuring the diameter of smooth plug gauges based on machine vision and laser caliper is proposed. The diameter of the gauge is measured by a laser caliper, and the machine vision module synchronously detects its posture in the light curtain, and corrects the measured values of the caliper. At the same time, the use of specialized tooling combined with an air flotation motion mechanism achieves automatic switching of multiple gauges and multi-position automatic measurement of a single plug gauge. The experimental results indicate that the repeated measurement standard deviation of the system is 0.16 μm. Absolute measurement error is less than 0.5 μm compared to the measured value of the vertical optical comparator. The measurement time for single end of the gauge is less than 45 s, which can meet the fast and high-precision verification requirements of commonly used plug gauges in production.