A UWB transmission apparatus that, in a system using a mixture of amplitude and phase modulation schemes, can support both of the amplitude and phase modulation schemes, while preventing the signal powers of amplitude-modulated signals from degrading. In this UWB transmission apparatus, if the modulation mode is of QPSK, a mapping part (121) selects one of four signal points on the IQ plane in accordance with a 2-bit data, and outputs information related to the I- and Q-components of the selected signal point to a QPSK/ASK modulated signal forming part (122). If the modulation mode is of ASK, the mapping part (121) selects the origin point on the IQ plane when the data being ‘0’ and selects one of four signal points on the IQ plane, similarly to the case of QPSK modulation, when the data being ‘1,’ and outputs information, which is related to the selected signal point, to the QPSK/ASK modulated signal forming part (122).