The present paper deals with some computations on the higher natural modes and the response of the hull vibration of a large tanker excited by propeller blade exciting force. The calculations are carried out under the assumption of the shearing vibration of the beam of variable cross section. The results of the response calculations are checked by which obtained from the generator survey on two tankers. The propeller blade exciting forces are estimated from the accelerations measured on several types of the large tankers in aid of the calculation. Also the allowable exciting force to maintain hull vibration within acceptable limit of an acceleration is estimated by the present calculation.