In nuclear magnetic resonance signal communication processing, filter plays an important role. This paper uses Cascade Integrator Comb (CIC) and FIR digital filter for multiprocessing. It makes full of the add operation of CIC filter, reduces a large amount of multiplication and System power consumption. At last it improves the operation speed of the system. After analyzing the CIC filter and FIR digital filter design principles, hardware was designed with FPGA. By using the MATLAB simulation, this paper selects the window function of FIR digital filter. Finally, this technique successfully used in nuclear magnetic resonance (NMR) logging instrument.