In Instant Casting movie System, a personal CG character is automatically generated. The character resembles a participant in a face geometry and texture. However, the voice of a character was an alternative voice determined by the gender of the participant. Therefore sometimes it's not enough to identify the personality of a CG character. In this paper, an automatic pre-scored voice assignment tool for a personal CG character is presented. Voice is essential to identify a personal character as well as a face feature. Our proposed system selects the most similar voice to the participants from voice database, and assigns it as a voice of CG character. Voice similarity criterion is presented by combination of eight acoustic features. After assigning voice data to a personal character, the voice track is played back in synchronization with the movement of the CG character. 60 voice variations have been prepared to our voice database. Validity of the assigned voice has been evaluated by MOS value. The proposed method has achieved 68% of the theoretical figure that is calculated by preliminary experiments.