An ultrasound inspection apparatus of the present invention includes: a probe provided with a plurality of elements； a transmitter configured to transmit the ultrasonic beam to an inspection object using the probe； a receiver configured to receive an ultrasonic echo signal from the inspection object； a sound velocity determiner configured to determine a sound velocity value inside the inspection object； and an element data processing section configured to generate a piece of second element data from at least two pieces of first element data using the sound velocity value, the piece of second element data corresponding to any of the at least two pieces of first element data, the sound velocity determiner being configured to obtain an optimum sound velocity value by optimizing the sound velocity value which is used when the piece of second element data is created in the element data processing section.
