To suppress an increase in transmitting power in a portable telephone having a multicall function by which a voice communication and a data communication can be performed simultaneously.

During a voice talk in a state that an obstacle is detected by a detection means (composed of a means (1) to detect that an earphone microphone 2 is not mounted on an earphone-microphone input terminal 3, a means (2) to detect that the voice level of a voice microphone 7 is at a threshold value or more and a means (3) to detect that the detection value of a distance sensor 9 is at a prescribed value of less) which detects the obstacle to worsen the transmitting efficiency of an antenna 6 at the portable telephone 1, a high- speed data communication is regulated, and the increase in the transmitting power is suppressed. Only when the obstacle is not detected, the data communication is permitted. As a result, the high-speed data communication is ensured stably without increasing the transmitting power.