To meet the demand that the conventional endoscope image has a narrow range of view and should be enlarged so as to include more tissues around it.

The medical image processing system includes an ultrasonic diagnostic apparatus 10 and an endoscope 12. The endoscope 12 will produce endoscopic images in a traditional way. In the ultrasonic diagnostic apparatus, arithmetic operation will be done on a processing start plane across the original point of observation and on a plurality of visual lines starting from the processing start plane. Then rendering will be done for the respective visual lines. By this, an ultrasonic image will be constructed. A coordinate operation will be done in reference to the coordinate data output from coordinate operation parts 24 and 54. For synthesizing the endoscopic image with the ultrasonic image, a correlative operation is used to determine the appropriate positional relationship of a user.