In order to overcome the shortcomings of the traditional binary image boundary tracking, including slow speed and leakage tracking, an algorithm of binary image boundary tracking and boundary chain code acquisition with strong generality is proposed based on the Freeman chain code. Based on the improvement of traditional Freeman chain code search algorithm, the average search direction is reduced to 2.5 when a new boundary point is found. Further the complex boundary segment is processed, and the starting point of the previous boundary chain is used as the starting point for the following boundary chain search, and fills the following boundary points, so that the image scanning from top to down and left to right is only one time to track all the boundaries, and eliminates the single pixel redundancy by setting the thresholds. The experimental results show that the proposed algorithm can effectively track the complex mesh boundary and internal holes, and it has the ability to remove the redundant points with anti-noise and faster speed.