1. An ultrasonic diagnostic apparatus comprising: a transmission beam generating unit that generates a plurality of sets of transmission beams by setting transmission beams which are transmitted in different transmission scan line positions and in which the sum of waveforms is 0, to one set; a reception beam generating unit that generates reception beams with respect to at least one reception scan line in consideration of transmission delay of the transmission beams in each of the transmission scan lines; a signal processing unit that extracts fundamental components and harmonic components from the reception beams, respectively; a synthesization unit that generates synthesized signals by synthesizing the fundamental components and the harmonic components according to a set synthesization ratio; and a display unit that displays a synthesized image comprising the synthesized signals.