With the rapid development of the software industry, the scale of software is becoming increasingly large, and the complexity of software is becoming increasingly high. As an essential part of software quality assurance (QA) system, software test has been gradually recognized more and more important by most software enterprises at home or abroad. Software reuse is an important technology to improve the efficiency of software development and to increase software quality. Usually academia and industry focus on applying software reusing concept to software demand engineering and design engineering, and have achieved remarkable results. Test reuse is to apply reuse thinking to software testing process, and to develop new tests by using results, knowledge and experience past accumulated in the process of software testing. Thanks to the characteristics and design principles of software testing, there exist in test design process many kinds of resources which can be reused possibly. However, few works are involved with this research. What’s more, there is not yet testing methods or tools that allow test developers easily to design new tests by reusing existed resources. Therefore, according to the XJIPC project “research of multilingual software test platform”, this thesis studies reuse of test cases and discusses related technology from three dimensions -- macro, detail, as well as implement of tool. At the end, a reuse-oriented test case library system has been constructed.