Many papers and books on improving voice quality exist around the world. This suggests that some people want to change their voice. However, there is a difficult image on improving voice quality. The reason is that objectively evaluating your own voice training is difficult. In this study, to improve the voice quality based on the user’s voice, we propose a method to create ideal voice heard from other’s using software UTAU and Interactive Differential Evolution. As result of the search and evaluation experiments, the evaluation values significantly increased from the initial to the final generations. These results showed that the proposed method has the possibility of making the ideal voice of the user. Furthermore, overall convergence was observed when in the transition of individual parameters. Especially, in the transition of the parameter related to voice formant, obvious convergence was confirmed in 13 out of all 14 subjects.