A modified CHMM model is proposed to improve the robustness of the speaker recognition system.In the modified model

the difference of the speech feature parameter was the observed vectors of the state-transitions of CHMM.Because of the modification

the dependence between frames was used in the modified CHMM.By the fusion of different features

the robust feature will dominate under the noisy environment and the delicate feature will dominate under clean environment.The experiments indicate that the modified CHMM have effectively improved the robustness of the speaker recognition system.