Abstract: Two modifications for speaker recognition system in noise environment are described. First, in order to improve the robustness of the system, noisy speech is decomposed into various frequency bands and de-noising is carried out by TEO in every frequency band. The wavelet coefficient is weighted according to the characteristics of speaker recognition, and is then transformed into MFCC. Second, in order to improve recognition performance and training speed, a modified OGMM that orthogonal transform is performed before EMarithmetic is applied at the recognition stage. Thus, it is not necessary to do orthogonal operation during every EM iterative process. The experimental results show that the parameters proposed have produced good effect and that modified OGMM can further improve recognition performance and training speed.