In the data transmission process of the spcaceborne radar, it is inevitable to be influenced by various interferences and get bit errors because of its working environment and highspeed transmission characteristics. In order to reinforce the highspeed signal and protect the process of transmission from disturbing, one of the perfect codes called golay code is taken and it can crrect include 3 error bits. Extended golay code can be created when a parity check bit is added at the end of golay code, by the way, its encode and decode curcuits were designed. Accoeding to the extended golay code generate matrix and parity matrix, as well as a hard decision decoding algorithm, the curcuits were implemented based on FPGA by verilog hardware description language, including parallel encoder/decoder and serial encoder/decoder. Finally, the behavior simulations showed that the extended golay code’s encoder could influently encod, at the same time the decoder could correct any combination within 3 bit errors when simulate the spaceborne radar was interfered and get error bits, it surely achieved the expected goal to reinforce the data transmission process.