Abstract: A Zhang's camera calibration method based on circular array calibration board was proposed. Firstly,using the Daheng mercury series camera to take photos to the different directions and different attitudes circular features calibration board,the shoots were carried out for 20 times. And a sub-pixel edge extraction algorithm was used to extract the edge of the feature in the image field of view. Then the received closed features were conditionally restricted respectively on circularity, eccentricity and convexity to extract the circular features in the images satisfied the requirements. Finally, the camera calibration was performed by mapping the pixel coordinates of the circular feature points on the calibration board to the world coordinates. Experiments results show that the average re-projection error of the center point coordinates of the circular featurecan be below 0.007 pixels, proving the feasibility of this algorithm.