Adaptive filter is a kind of filter which can modify its parameters in real time according to the noise characteristics, so as to achieve the best filtering effect. Designed a complete adaptive filter device. At first, use the adder and the phase shifter circuit to deal with the noise mixed with original signal. Then import the mixed signal in a FPGA module after AD transform, and complement a least mean square error (LMS) algorithm for adaptive filter on FPGA platform. Finally, export the output signal after DA conversion and it can be observed on the oscilloscope. The experimental results show that the adaptive filtering scheme can effectively filter sinusoidal wave, triangular wave and gaussian noise which are more than 10Hz differ from the original signal in the frequency range of 1-200KHz.