Neither error nor interrupt was allowed in natural examination, to insure the exam be fair-minded and timely. While in the practical application of exam system, there were fault of data and interrupt of process, due to several problems on function or security, so how to ensure the normal circulation of exam system effectively becomes an important research topic recently. In this paper, based on client / server (C / S) test system, started with security, through the technologies of fault tolerate in main and spare servers、double servers push-and-pull communication、mongline manage and invalid check in client, the management of fault tolerate in exam system was designed and realized, which can enhance the reliability and usability of examination system.