A communication terminal device is operable to multiplex a plurality of channel signals based on TFC (Transport Format Combination) selected by performing a TFC selection and transmit it. The communication terminal device includes a storage unit operable to store a plurality of combination of classifications to which the gain factors belong, as a combination of gain factors for weighting each of the plurality of channel signals, and to store a quantity of reduction of a maximum transmission power when the plurality of channel signals in association with each combination of the plurality of classifications are multiplexed and transmitted, and a TFC selection unit operable to select the TFC by reading out the quantity of reduction in association with the combination of the classification corresponding to the combination of the gain factors in each TFC from the storage unit when the TFC selection is performed.