Abstract: In UWB-IR signal detection, FHN model detection method performance is limited by the minimum detectable signal to noise ratio(SNR). From this point, wavelet packet is introduced into FHN model. In addition, the shortcoming of traditional single threshold wavelet packet is analyzed, combined with the new piecewise threshold wavelet packet, a novel UWB-IR signal detection method based on wavelet packet and FHN model is proposed to detect UWB-IR signal. Furthermore, the performance of the proposed algorithm is simulated and analyzed. Simulation results shows that the proposed algorithm reduce the detectable SNR and improve the detection performance of FHN model detection method. Therefore, the UWB-IR signal can be detected effectively under strong noise.