Nowadays, students’ misconceptions about many subjects have been determined, and new teaching approach has been tried to change the misconceptions by conducting studies on science education area. Misconceptions may occur because of didactical, epistemological, ontogenetic or cultural obstacles. The main purpose of this research is to determine the causes of the fifth grade students misconceptions originated from didactic about digestive system. The misconceptions originated from didactic were revealed by the analyses of the pre and post tests. Then, the data concerning the student, teacher and knowledge which were regarded as the main elements of the didactical environment, were collected. The causes of the misconceptions originated from didactic were determined by the analyses of the curriculum, textbooks, course records and interviews conducted with students. It was suggested that misconceptions originated from didactic can be prevented by reorganizing the teaching environment and uncovering the causes of those misconceptions.