Abstract: A mobile communication terminal includes: a signal transmission section having a predetermined default value for a transmission characteristic; an antenna to be used at least by the signal transmission section; a separate circuit section sharing ground with the signal transmission section and the antenna, and being different from the signal transmission section; a monitoring section monitoring a change in a use state of the terminal related to the separate circuit section; and when the signal transmission section transmits a signal using the antenna, if the monitoring section detects a change in the use state of the terminal, a transmission-characteristic adjusting section adjusting a transmission characteristic of the signal transmission section from the default value to a characteristic optimized for the use state.