The basic technology real-time signal processing arithmetic and hardware architecture of infrared image detecting system were presented.Aiming at a large view field infrared detecting system,the real-time processing arithmetic principle and flow,which are applied to omnidirectional infrared target search,were proposed.The scheme of applying high-performance DSP,FPGA and CPCI bus technology was used to compose a signal processing system which has powerful processing capability,high-speed and reliable interface.The experimental result shows that the large field infrared image detecting real-time signal processing system works reliably and stably,and it has achieved the demand of high performance.