For analyzing the propeller vibratory bearing force and moment of a self-propelled model, it is necessary to obtain the thrust and torque force variations of a blade of the multi-bladed propeller which rotating in ship wake. This paper presents a method of direct measurement of these force variations by the use of two strain gauges applied at the surface of the root of the blade. The.hydrodynamic force induced by the propeller blade is separated from total force included centrifugal force of the blade by attempting the strain measurement of the rotating propeller in air. The thrust and torque forces are obtained from the two strain components produced by the above hydrodynamic force measured by the two strain gauges. The so-called wake bearing force and moment are easily calculated from the Fourier components of the thrust and torque variations of one blade of the multibladed propeller obtained by the method mentioned above. As an example of the present experiment, the wake bearing forces and moments of four, five and six bladed propellers of a container model are illustrated. It is of interest that considerable discrepancies appear in the phase lags of the peak of force variations between the results of the quasi-steady method using the wake distribution curve and the present unsteady force measurements of the thrust and torque variations.