To increase the synthesized accuracy of the multi-beam sounding system not only requires to increase the far-field accuracy, but also not to neglect the near-field accuracy. In view of the adoption of the far-field approximation model in the multi-beam sounding system, it made the near-field accuracy sharply insufficient and multi-beam real time kinematic focused beam-forming method on the basis of FPGA was introduced. The method imported the phase shifting focused beam-forming, and proved its feasibility to solve the near-field problem in the multi-beam sounding system, meanwhile, profoundly analyzed the real time processing of each influential factor, and proposed a real time processing structure on the basis of FPGA, in which the structure completed RT-DFBF on the condition of 80 input passages, sampling rate of 28kHz and 128 beams. The pool experiment result testifies the effectiveness and feasibility of the method, and possesses some engineering value.