Abstract: With the development of the information technology and network communication, the increased security demands should be satisfied in the network communication applications. Reconfigurable computing is a novel computing system which can combine the reconfigurable hardware processing unit and the software programmable processor. The design of a cipher processing system adopts reconfigurable computing technology, which can support multiple cryptographic algorithms in the cipher application. Therefore, it can achieve crypto algorithms processing with efficiency and flexibility, and it also solves the hidden trouble in the cipher processing system. Based on the analysis of processing structure characteristics of popular block cipher algorithms, the authors propose a reconfigurable cipher processing architecture (RCPA) using the design method of reconfigurable processing architecture. And a prototype is implemented based on RCPA. The prototype is realized using Altera’s FPGA. The logic synthesis, placement and routing of RCPA are accomplished using 018μm CMOS technology. The experiment results indicate that on the prototype based on RCPA, the performance of many block ciphers is 10~20 times higher than on highperformance general purpose processor and 1.1~5.1 times higher than on other specialized reconfigurable frameworks. The results prove that RCPA can guarantee high flexibility for most of the block cipher algorithms and can achieve relatively high performance.