Uchida & Nakaune (2004) investigated the influence of utterance speed and pitch on personality impression. However, Uchida et al. (2004) did not limit the speaker’s sex and utterance context. The present study examined the influence of utterance speed and pitch in female first-time self-introductions on impression formation and whether personality impression can be estimated from voice impression (impression of the speaker’s voice and her condition). The experiment was a 3-factor mixed design with listener’s sex (male, female), utterance speed (fast, normal, slow), and pitch (high, mid, low) as independent variables. Results indicated that utterance speed and pitch have independent influences on impression formation in female first-time self-introductions, and that personality impression can be estimated from voice impression. In particular, Extroversion and Openness to Experience can be readily estimated from voice impression, while Conscientiousness cannot.