Availability is one of the key features for transaction processing systems. Fault injection is one of the important techniques to hasten availability tests. A fault injection platform is designed in this paper for IA64 system which is being widely used in transaction processing business. The fault injection platform is implemented using client/server mode and a series of fault injection tools are accomplished which covers CPU faults, memory faults, disk faults, IO faults, file system faults and system call boundary errors. A group of experiments on a typical IA64 server are described and performed, and the experiment results validate the effectiveness of the fault injection platform.