A new method for infrared (IR) warning system to recognize small targets in IR image sequences in real time in complicated IR background was presented. The system employs two dimensional digital filtering using Field Programmable Gate Array (FPGA), parallel processing of high speed Digital Signal Processor (DSP) and target recognition algorithm based on target movement analysis. The system not only improves dim moving target capture capability in complicated background, accomplishes moving multi target automatic recognition, but also is capable of target overlapping prediction and target recapture. The system processing rate reaches 25 frames per second, and the system responding time is less than 1 second.