Abstract: Objective The digital subtraction angiography (DSA) image is processed to obtain central line and bifurcation point of coronary artery, and angle between blood vessels. Methods The image is processed on the platform of Matlab. The central line of coronary artery is extracted by Hessian matrix. The coordinates of the bifurcation point and two other points on branch vessels are obtained by central line matrix of DSA image. Then average angle of coronary artery vessels is calculated by the three points. Results For randomly selected DSA images, high accuracy values of coronary artery central line and angle may be obtained. Conclusion Accurate measurement of coronary artery vessel angel may help operators of DSA in setting body position and help researchers in image processing.