To generate an acoustic velocity map minimizing an influence of such structures as blood vessels, as much as possible in a short time.

A region 112 of interest is set on a B mode image 110 displayed on a display unit. Ultrasonic waves are transmitted and received in a Doppler scan mode to generate color Doppler information in the region 112 of interest. A region excluding a moving object region 117 in the region 112 of interest is determined as an acoustic velocity measurement region 119 on the basis of the color Doppler information. A plurality of promotion focal points 125 are set in the acoustic velocity measurement region 119 to transmit/receive ultrasonic waves, and RF data corresponding to the acoustic velocity measurement region 119 are generated. A local acoustic velocity value is calculated based on the RF data corresponding to the acoustic velocity measurement region 119 so as to generate an acoustic velocity map of the acoustic velocity measurement region 119.