This study examined the plagiarism rates of student teachers (hereafter students) during the distance education process and investigated the reasons for plagiarising. Qualitative dominant sequential exploratory design was used. The sample consisted of students studying at two different universities in Turkey. The study group was determined in two stages as a quantitative sample and a qualitative participant group. To select the quantitative sample, the maximum diversity sampling was used, while the criterion sampling method was utilized for the qualitative participant group. The data were collected in two stages as quantitative and qualitative in accordance with the nature of the mixed-methods research. In the first stage, the assignments prepared by students were included in the plagiarism program and their similarity rates were determined. All assignments were coded according to the names of the students who prepared them. Then, the assignments with the highest and lowest rate of plagiarism were identified. In the next stage, qualitative data were collected through semi-structured interviews conducted with the students who prepared the aforementioned assignments. The interview questions were prepared to obtain in-depth information about why they plagiarized or did not plagiarize. Content analysis was applied to analyse the data, and meaningful findings were found. The findings were collected under five headings. According to the results, those with high plagiarism stated their reasons for plagiarism as their economic and social conditions were not suitable for research. On the other hand, those with low plagiarism considered plagiarism as an action such as stealing and being unfair.