Aims: This study was conducted to determine the risk perceptions of patients with type 2 diabetes mellitus (T2DM) regarding insulin therapy and diabetes complications.Background: Self-care behaviour is an important requirement for managing T2DM, and risk perceptions are thought to play a key role in this behavioural process. It is predicted that an accurate risk perception will contribute to diabetes management and the reduction in diabetes-related complications.Design: This study was conducted as cross-sectional and a descriptive study. The STROBE checklist was used. Methods:The study was conducted with 330 patients with T2DM who presented to the endocrinology outpatient clinic of the Eskisehir City Hospital between October 2020 and May 2021. A personal information form, the Insulin Treatment Appraisal Scale and the Risk Perception Survey-Diabetes Mellitus were used to collect data. The SAS 9.4 software package was used for the statistical analysis. Data were evaluated using descriptive statistics, the Mann-Whitney U test, the Kruskal-Wallis test and the Spearman correlation analysis.Results: It was determined that 62.4% of the patients with T2DM participating in the study were female, the mean age was 56.7 ± 9.1 years, 50.6% were primary school graduates, 31% used oral antidiabetic medications, and 58.7% used insulin together with oral antidiabetic drugs. The mean score of participants on the total Insulin Treatment Appraisal Scale was 75.1 ± 11.5, and the level of negative perceptions towards insulin use was found to be high. The participants' mean score on the total Risk Perception Survey-Diabetes Mellitus was 3.9 ± 0.8, and it was found that they had high levels of risk perceptions of diabetes complications. There was a moderate, statistically significant negative correlation between the Insulin Treatment Appraisal Scale and the Risk Perception Survey-Diabetes Mellitus. Conclusion:Patients with perceptions of a lower risk for diabetes complications had more negative attitudes towards insulin therapy. It is recommended to determine the risk perceptions of patients with T2DM and to plan appropriate nursing interventions that can increase their positive perceptions and change their negative perceptions so that they can make healthy behaviour changes. Additionally, it is recommended