The purpose of this study was to examine the effect of creative and critical thinking based laboratory method on prospective primary teachers' creative and logical thinking abilities. This research was conducted with 90 prospective elementary school teachers who were enrolled in two classes of education faculty during the spring semester of the 2004-2005 academic year. Creative and critical thinking based laboratory applications were conducted in the experimental group, and traditional laboratory applications were conducted in the control group. As a result of the investigation, it was determined that the experimental group was more successful than the control group in terms of the logical thinking ability and creativity. Implications for science education at the teacher education level were discussed. (Contains 8 tables.)