The purpose of this study was to analyze the relationship between peer evaluation and self-evaluation about practical teaching competence that appears in pre-service science teachers teaching demonstration process. Also this study attempted to investigate the relationship among self-evaluation, peer evaluation and pre-service science teachers level of teaching performance. The participants of this study were 63 second, third, and fourth year students in college of education. These pre-service teachers were taking courses related to science education. In this study, the fact that the agreement tendency between self-evaluation and peer evaluation was very high shows that pre-service science teachers do not show self-leniency in self-evaluation. To investigate whether there was a difference in performance level by group depending on agreement between self-evaluation and peer evaluation, this study conducted one-way ANOVA. The analysis results showed there was a significant difference in the performance level that represented practical teaching competence in teaching demonstration depending on groups by agreement between self-evaluation and peer evaluation. The results of Scheffe test especially shows that there is a difference between the agreement group (H) and the agreement group (L). This study shows the approach using agreement between self-evaluation and peer evaluation in evaluation about pre-service teachers practical teaching competence is effective. This study suggests that the use of self-evaluation and peer evaluation is effective in evaluating the practical teaching ability of pre-service science teachers. Therefore, it is meaningful to induce the pre-service science teachers to give an opportunity of reflective thinking and to recognize their performance level correctly by actively introducing self-evaluation and peer evaluation in teacher education course.