An ultrasonic imaging system, an ultrasonic imaging device, an ultrasonic imaging method, and an image synthesizing program are provided which can obtain an accurate synthesized image, even if a specimen has a surface with a large curvature. An ultrasonic imaging system may include a probe, an image generator, a spatial relationship calculating module, and an image synthesizing module. The probe may perform scan of first and second ultrasonic waves different from each other. The image generator may generate a first ultrasonic image based on the first ultrasonic wave and generate a second ultrasonic image based on the second ultrasonic wave. The spatial relationship calculating module may calculate a spatial relationship based on two first ultrasonic images at two positions and two second ultrasonic images at the two positions. The image synthesizing module may synthesize one of the first and second ultrasonic images at one of the two positions with the one of the first and second ultrasonic images at the other position based on the calculated relationship.
