The present invention provides ultrasonic diagnostic equipment for accurately determining a three-dimensional picture generation start depth, independently of a turbidity degree of an amniotic fluid and the like, which exist between a three-dimensional picture generation target such as an fetus and the like and a portion that is not the three-dimensional picture generation target such as a placenta or an uterine wall or the like serving as the obstacle of the fetus. In the present invention, the brightness values in the depth direction of an ultrasonic received signal are cumulated, and the depth direction of the ultrasonic received signal is divided into a plurality of depth zones S0 to S9 so that the respective cumulative addition values become the approximately same values, and among the depth zones S0 to S9, the plurality of higher depth zones having the longer zone length are selected as three-dimensional picture generation start candidate zones, and among the three-dimensional picture generation start candidate zones, the three-dimensional picture generation start candidate zone having the shallowest depth is selected as a three-dimensional picture generation start zone S, and a predetermined depth inside the three-dimensional picture generation start zone S is determined as a start depth A of the three-dimensional picture generation.