Highly Accelerated Life Testis a method to find out the products defect, it can expose the defect of tested sample through accelerating environmental stress bring stress on the product and gradually increase the stress to find the defect of product, then focus on the defect during the test and improving the productanalyzing and correcting the defects from design, technology and material and so on, to improve the reliability of the product. . The most important characteristic of this kind of test is bringusing high stresshigher environmental stress to the product to shorten the tesing time, it means that the protermined testing time is represented the normal operating time.