An objective of the present invention is to provide an ultrasound system which can correct a positive-negative asymmetry in pulse inversion (PI) and obtain a high-image quality ultrasound image. To carryout an asymmetry correction of a transmission assembly circuit comprising an oscillation adjustment amplifier (10) and an ultrasound oscillator array (90), correction data obtained in a calibration mode is stored in a correction memory (46), and positive-negative asymmetry of an overall receiving assembly circuit comprising a computation unit (45) is corrected in a diagnostic mode of the device using the correction data.
