There are provided transducers, transmission pulse generators for transmitting pulses to the transducers, a transmission power source for supplying power to the transmission pulse generators, and an output side capacitor 7 for stabilizing a voltage of the transmission power source. The transmission power source includes a plurality of mode-specific power sources 1A and 1B for outputting a constant voltage, and a mode changeover switch 6 provided between the mode-specific power sources and the output side capacitor. The transmission power source further includes a power supplying power source 2 connected to the mode-specific power sources for supplying power, and a power regeneration capacitor 4 with a larger capacity than that of the output side capacitor, one electrode terminal of which is connected to a connection point between the power supplying power source and the mode-specific power sources and the mode changeover switch, and the other electrode terminal of which is connected to ground. The mode changeover switch is capable of connecting the power regeneration capacitor, instead of each of the mode-specific power sources, to the output side capacitor. There is provided an ultrasonic diagnostic apparatus that reuses power stored in the output side capacitor to reduce power consumption.