To provide an ultrasonic diagnostic apparatus having reduced deterioration of an image due to joints of diagnostic images in a composite image formed by composing the diagnostic images.

This ultrasonic diagnostic apparatus includes a transmitting/receiving means transmitting/receiving ultrasonic waves and acquiring a receiving signal, an image formation means 2 forming diagnostic image data from the receiving signal, a display means 6 displaying the diagnostic image data as the diagnostic images, a recording means 3 recording the diagnostic image data, a composite means receiving a plurality of pieces of diagnostic image data at lease one of the image formation means 2 and the recording means 3, displaying them as a plurality of diagnostic images on the display means 6 and composing the plurality of diagnostic images, and an input means 7 capable of transmitting a command to the recording means 3 and the composite means 4. The composite means 4 includes a position adjustment means 5 adjusting the display positions of the plurality of diagnostic images displayed on the display means 6 according to the command of the input means 7.