Abstract:The application of embedded software on engineering mechanical equipment becomes more and more popular, to ensure the high quality and reliability of software product, software test is required to minimize the bugs. The development environment and operation environment of embedded software are different, which increase the difficulty of software test. Using embedded software of a certain type of diagnostic instrument as study subject, first analyze requirements for the measured software, divide the test types into man-machine test, functional test, interface test, boundary test and performance test. Then built and describe the simulation test environment based on feature of runtime environment of diagnostic instrument software, and expound the correlative test methods specifically against different test types. Finally use presented test method to execute test cases, it can be seen from the test result that presented test method can find software problems effectively, and have certain practical value.