According to one embodiment, a first unit includes a first ultrasonic image generation unit generating a first ultrasonic image at a first processing speed and with a first processing function based on a reception signal, a connection unit detachably connecting the first unit to a second unit, and a connection detection unit detecting connection between the first and second units. The second unit includes a second ultrasonic image generation unit having a second processing speed faster than the first processing speed and a second processing function higher than the first processing function and generating a second ultrasonic image having larger data than the first ultrasonic image based on the reception signal upon detection of the connection.
