In this study, the purpose was to make use of metaphors to determine the difficulties experienced by secondary school 6th and 7th grade students in the process of learning the subject of circle. In the study, the phenomenological research design, one of qualitative research methods, was used. The research data were collected from a total of 140 secondary school students (80 6th grade, 60 7th grade), who were asked to fill in the blanks in the statement of "While learning the geometric shape of circle, I experience the biggest difficulty in …. because …". For the analysis of the data, content analysis method was used. The results revealed 42 different valid metaphors. These metaphors were gathered under seven categories. Among these categories, the most frequently produced ones were "problems related to the shapes drawn in a circle and tangent problems with circles." Moreover, in the study, it was found that when compared to the 6th grade students, the 7th grade students produced more metaphors related to the difficulties experienced in the teaching process of circle. Based on all these results and the students' perceptions, suggestions were put forward regarding the development of students' positive perceptions and understanding of geometry teaching.