The purpose of this study is to explain prospective science and technology teachers' pedagogical content knowledge (PCK) about the cell. Lesson preparation, laboratory plan, interview with teacher candidates, and concept mapping were used to collect the data for prospective teacher's PCK. The study was conducted with six prospective science and technology teachers in the spring of 2006-2007 in Pamukkale University-Turkey. We aimed to identify the content and structure of the PCK for a topic on cell, describing the PCK in terms of relations between four different aspects: Knowledge about science and technology curriculum, belief about subject matter knowledge, knowledge about students' understanding; knowledge about assessment of students. According to the result of the study, pre-service teacher's knowledge inaccurate special teaching methods, they used a teacher-centered approach, and also they have a high belief of subject matter knowledge. Based on the result of this study, which were discussed in the light of national and international literature, we have suggestions for further researchers, curriculum developers, and science and technological teacher educators. (Contains 1 table.)