In an ultrasonic imaging apparatus, image quality is improved without increase in the number of ultrasonic transducers. The ultrasonic imaging apparatus includes: a transmitting unit for supplying drive signals to plural ultrasonic transducers so as to form an ultrasonic beam having a beam width that covers adjacent two or more transmission lines a receiving unit for performing phase-matching processing and addition processing on the reception signals to generate RF data in which focuses of ultrasonic echoes are narrowed in positions corresponding to respective pixels of an ultrasonic image to be displayed an RF data storage unit for storing the RF data with respect to a plural number of transmissions of the ultrasonic beams and an image signal generating unit for averaging the RF data for the plural number of transmissions and generating an image signal representing the ultrasonic image based on the averaged RF data.
