Abstract: In order to improve the efficiency and reliability of the ultrasonic testing, a type of ultrasonic testing instrument of high ratio of performance to cost was developed successfully. With the help of Embedded Computer and taking full use of the traditional ultrasonic testing device, USB, electronic technology and digital signal processing, the system realized data collection, save, display, analysis and processing. It showed the advantage of small, low-cost, plug and play, stability, high rate, efficiency and reliability. A very good foundation for the developing of imaging，intelligent and automation of ultrasonic testing was established by this device.