Abstract: The article combines the computer application and ultrasonic flaw detection technique, and describes a software design of ultrasonic testing system based on Linux and Qt/Embedded. The study of this paper places emphasis on the key technologies for the realization of software system and gives special details of their solutions, including the real-time transmission of data, the storage and USB output of file, the real-time display of waveform and so on. The performance tests showed that the proposed schemes in practical applications had good application results, they could meet the systems real-time requirements and raise the system efficiency and meanwhile enhance the user experience.