A newly developed voice personality transformation algorithm is introduced in this paper. Voice personality transformation is the process of changing one person's acoustic features (source) to those of another person (target). In this paper, personality transformation is achieved by changing the LPC cepstrum coefficients, excitation spectrum and global/local pitch contour. An orthogonal vector space conversion technique is proposed to transform LPC the cepstrum coefficients. This technique consists of principle component decomposition by applying the Karhunen-Loeve(KL) transformation and minimum mean-square error coordinate transformation(MSECT). To transform prosodic characteristics, we propose a simple pitch contour modification method. The experimental results show the effectiveness of the proposed algorithm in both subjective and objective evaluations.