In this study, it was aimed to determine the effect of Project Based Instruction on teacher candidates' academic self-concept, and attitudes towards the course. Revised Bloom taxonomy was used in planning of the course. The study was carried out in the "Instructional Design" course within the Undergraduate Program in the Department of Computer and Instructional Technologies in Ege University through 12 weeks period. In the research, a pre-test post-test control group experimental design was used. The students who took this course in the 2006-2007 academic years constituted the participants of the study. Since the students took this course in two sections, one of the sections was randomly assigned as the experimental group (n=37) while the other as the control group (n=35). Covariance analyses were used to compare the groups in terms of dependent variables. The results demonstrated positive effects of project based instruction on students' academic self-concept and attitudes.