The invention provides a medical image diagnostic apparatus capable of mitigating the load of operation of when measurement is carried out using a medical image. [MEANS FOR SOLVING PROBLEMS] An ultrasonograph (100) acquires input image information which is data on an image of a subject and holds it in a storage section (3). An image selecting section (8) carries out image recognition calculation using the input image information and the past image information in an image measurement database (7). If image recognition is successful, a measurement position setting section (9) refers to the record of the image measurement information including the part image information most similar to the input image information, takes out the measurement position information on the record, and determines the measurement position. A measurement position determining unit (6) superimposes the measurement position on the input image information (21) on a display section (12). A measurement calculating section (11) carries out measurement calculation of the measurement position determined by the measurement position setting section (9) and displays the measurement results on the display section (12). A measurement position determining unit (6) updates the image measurement database (7) according to the input image information, measurement position determined by the measurement position setting section (9), and so forth.