A base station of the present invention performs transmission power control quickly with maintaining communication quality in mobile communications systems, by setting up priority about transmission power control and performing transmission power control sequentially from a channel with a high priority. A channel priority setting unit outputs priority information indicating priority for transmission power control about a plurality of channel information. A power calculation unit outputs total power information of all channels about the plurality of channel information. A power adjustment unit performs power adjustment to the channel information selected on the basis of the priority information when the total power information has larger value than maximum transmission power information.