A vacuum circuit breaker comprising a circuit breaker body mounted on a carriage configured to move within a cradle inserted into a switchboard, the circuit breaker body being provided with a control power connector detachably connectable to a control power plug provided in the switchboard, the vacuum circuit breaker further comprising a withdrawal interlock device comprising: a link configured to move according to whether the control power plug is attached to or detached from the control power connector; the withdrawal interlock device characterized by: a link connector connected to the link to move in linkage with the movement of the link; a first lever connected to the link connector to rotate by a predetermined angle according to the movement of the link connector; a moving plate configured to block movement of the carriage from an inside of the cradle to an outside thereof by moving in response to rotation of a second lever; and a second lever located between the link and the moving plate and configured to rotate by a predetermined angle and push the moving plate so as to prevent movement of the carriage, the second lever being brought into contact with the first lever and the rotation of the second lever back to an original position being prevented, such that the moving plate is maintained at a blocking position thereof, when the first lever is rotated by the link connector in response to the control power plug and the control power connector being connected to each other. a link configured to move according to whether the control power plug is attached to or detached from the control power connector; the withdrawal interlock device characterized by: a link connector connected to the link to move in linkage with the movement of the link; a first lever connected to the link connector to rotate by a predetermined angle according to the movement of the link connector; a moving plate configured to block movement of the carriage from an inside of the cradle to an outside thereof by moving in response to rotation of a second lever; and a second lever located between the link and the moving plate and configured to rotate by a predetermined angle and push the moving plate so as to prevent movement of the carriage, the second lever being brought into contact with the first lever and the rotation of the second lever back to an original position being prevented, such that the moving plate is maintained at a blocking position thereof, when the first lever is rotated by the link connector in response to the control power plug and the control power connector being connected to each other. a link connector connected to the link to move in linkage with the movement of the link; a first lever connected to the link connector to rotate by a predetermined angle according to the movement of the link connector; a moving plate configured to block movement of the carriage from an inside of the cradle to an outside thereof by moving in response to rotation of a second lever; and a second lever located between the link and the moving plate and configured to rotate by a predetermined angle and push the moving plate so as to prevent movement of the carriage, the second lever being brought into contact with the first lever and the rotation of the second lever back to an original position being prevented, such that the moving plate is maintained at a blocking position thereof, when the first lever is rotated by the link connector in response to the control power plug and the control power connector being connected to each other.