To provide the transmission control method of a broadcasting satellite capable of ensuring a predetermined service time rate while suppressing an increase in magnitude of the broadcasting satellite, and to provide a system thereof.

In the transmission control method of a broadcasting satellite, compensation amount for rainfall attenuation in each of a plurality of areas is calculated from precipitation data to be collected at a predetermined time interval, the phase and amplitude value data of an array radiation element are generated on the basis of the compensation amount for rainfall attenuation in each of the plurality of areas, and the radiation pattern of a phased array antenna of the broadcasting satellite is varied on the basis of the phase and amplitude data of the array radiation element. In this method, the amount of short-time variation margin for compensating the rainfall attenuation, if rainfall exceeds the compensation amount for rainfall attenuation within the predetermined time interval in each of the plurality of areas is calculated from the precipitation data to be collected in the predetermined time interval, and the phase and amplitude value data of the array radiation element is created on the basis of a compensating amount in which the short-time variation margin is added to the compensating amount for rainfall attenuation for each area.