An ultrasonic image capturing apparatus is disclosed for transmitting ultrasonic pulses from an ultrasonic probe in which elements are arranged two-dimensionally to a subject, receiving the ultrasonic pulses reflected by the subject, and displaying a slice image of the subject. A vector Doppler processor detects motion of the subject along the direction of an aperture of a receiving beam former, and a displacement detector detects motion of a focus region in the subject based on a result of computation of the vector Doppler processor. A scanning plate setting section determines an image capturing region by using ultrasonic waves by the displacement detector.