An ultrasonic imaging apparatus includes a plurality of transducers that transmit ultrasonic waves and a transmission unit that supplies drive signals to the plurality of transducers. An amplitude control voltage generation unit and a transmission circuit unit are connected to a common voltage power supply. An amplitude control voltage generation unit receives an output voltage of the voltage power supply and an attenuation degree setting signal instructing an attenuation degree of the drive signal for each of the transducers for weighting of the drive signal, and generates an amplitude control voltage corresponding to a voltage obtained by attenuating the output voltage by the attenuation degree. The output voltage of the voltage power supply is reduced to a voltage corresponding to the amplitude control voltage, and a drive signal having a predetermined waveform is generated whose amplitude is the voltage after the reduction for each of the transducers.
