An ultrasonic diagnostic apparatus of the present invention includes a signal transmission section, which supplies a driving pulse to a transducer in order to transmit an ultrasonic transmission signal to an object and transmits to the object a non-inverted component and an inverted component of an ultrasonic waveform, and a signal processing section, which removes a fundamental wave component by adding received signals from the object. The signal transmission section includes a switching section which changes an output period within a half period of the transmission signal according to at least one of a load connected to the signal transmission section and amplitude, a frequency, and a wave number output from the transmission circuit.