Abstract: In order to provide hearing protection and speech enhancement of environmental sound sources from different angles in a strong noise environment, an improved generalized cross correlation（GCC） delay estimation method, which is based on spectral subtraction is used to synchronize the signals received by the microphone array. By combining the synchronized array signals with the speech enhancement algorithm based on generalized sidelobe canceller（GSC） for active noise insulation earmuff, noise suppression and speech enhancement can be achieved. First,based on the GCC algorithm, the spectral subtraction of multi-window spectral estimation is introduced as the signal preprocessing link to improve the signal to noise ratio of the signal received by the microphone for algorithm improvement. Then, the simulation results of different weighting functions are compared and analyzed for the improved time delay estimation algorithm. Finally, the delay compensation of the microphone array signal is performed based on the time delay estimation results, and the noise suppression and speech enhancement effects of the improved speech enhancement algorithm are analyzed. Compared with the algorithm before improvement, the quality of the output speech signal is significantly improved in different noise environments.