A vacuum circuit interrupter comprising in a vacuum vessel at least a pair of separable stationary electrode and a movable electrode, and a main shield surrounding the electrodes. The axial length L of the main shield is greater than T.sub.1 and smaller than (T.sub.1 +T.sub.2 tan 45.degree.), where T.sub.1 is the distance which is the sum of the gap length between the electrodes when the electrodes are separated and the thicknesses of the electrodes, and T.sub.2 is the shortest distance between the main shield and the electrodes.