Miniature servo motors are widely used in robotics, industrial manufacturing, and other fields, where the angular precision is a key indicator of performance. Traditional contact measurement methods suffer from mechanical wear and limited accuracy, while machine vision, as a non-contact measurement method, has the advantages of interference-free and high-precision measurement. This paper proposes a machine vision-based angle measurement method for miniature servo motors. First, the zero position of the servo motor is aligned with the device’s zero reference through mechanical design. Then, the captured image is corrected using positioning markers on the base. Finally, the actual rotation angle is calculated by identifying the coordinates of the rotation axis center and the pointer tip. Experimental verification shows that this method has a small average absolute error and stable precision, which can meet the application requirements for high-precision angle measurement and has good reliability and practical value.