Abstract: The radiation characteristic of a shaped beam reflector antenna subjected to a single-hole damage is studied. The far field of the shaped reflector antenna is modeled and analyzed using the method of physical optics based on surface current integration. Comparisons between the calculated results and those measured before the damage were made, and good agreement has been found to exist. A study was then made on the radiation pattern characteristics of the antenna after its reflector is damaged by bomb explosion, including the influence of the size and position of the damage. The larger the size and the closer the position of the damage hole to the reflector center, the higher will be position of the side lobe and the lower will be the gain of the antenna.