Due to the nature of RME, which sees mathematics as a human activity, there is never a fixed and complete theory for mathematics education. Therefore, it is seen as an approach that still needs to be developed. The aim of this research is to analyze the RME (Realistic Mathematics Education) activities prepared by the pre-service primary school teachers who were educated with a constructivist approach. Participants were 137 student teachers who have been trained with a constructivist approach for about 15 years and will teach with this approach. It was determined that the activities prepared by the pre-service primary school teachers were generally at a medium-level in terms of compliance with RME. The results of the research show that no matter how much education they had, the effects of constructivist education could not overcome some traditional patterns in pre-service teachers. In addition, the training they had about RME was not enough to break these patterns. It has been observed that pre-service teachers are insufficient in preparing activities for the basic principles of constructivism with RME. This shows that the disruption in the education system started at the undergraduate level. With this beginning, an endless cycle is formed. In order to avoid the basic patterns brought by traditional education, learning approaches such as the RME approach in addition to the constructivist approach should also be employed at lower grade levels.