This research aims to determine the main problems that primary school students encounter during the adaptation process to school in line with teachers’ views. The research question was determined as “What are the main problems that primary school students encounter during the adaptation process to school and how do teachers evaluate these problems?” Semi-structured interviews were conducted with 15 classroom teachers using the phenomenological research model. The data were examined using the content analysis method and the findings were divided into four main categories: emotional and social adaptation problems, academic adaptation problems, problems related to teacher and family interaction, and behavioral adaptation problems. According to the findings, it was determined that the students experienced adaptation difficulties such as school anxiety, difficulties in separating from the family, and difficulties in focusing on lessons. It was found that teachers emphasized obstacles such as lack of family cooperation and difficulties in adapting to classroom rules. It is suggested that teachers, family support, and in-school interaction should be increased in order to solve these problems. The results of the research serve as a guide for teachers and education policies and may contribute to the improvement of teaching methods and school support systems.