Background Patients with type2 diabetes frequently face prejudices that result in feelings of stigma, creating an adverse feedback loop that both degrades their quality of life and complicates the management of their illness. The aim of this study is to determine the relationship between stigma and illness acceptance in type 2 diabetes mellitus and the factors that determine it. Methods The research was conducted as a cross-sectional descriptive study and between January and June 2025 at the endocrinology clinic of an university hospital.The study included 96 patients. Data were collected using a personal information form, the Type 2 Diabetes Stigma Assessment Scale (DSAS-2), and Acceptance of Illness Scale (AIS).The data were analysed using IBM SPSS 25.0 software. A STROBE checklist was the reporting guide for this study. Results Participants'DSAS-2 and AIS total mean scores were 46.56 +/- 14.44 and 22.93 +/- 6.25, respectively. A positive correlation has been determined between DSAS-2 and AIS scores. (R = 0.560, p < 0.001). Participants who had diabetes for 6-11 years, received combination therapy (insulin and oral antidiabetic agents), were hospitalised due to DM in the past year, and required assistance with care had higher DSAS-2 and AIS scores compared to others (p < 0.05). Multiple regression analysis showed that the type of diabetes treatment was a significant determinant of DSAS-2 and AIS scores. Conclusion Patients receiving combination therapy demonstrated significantly higher stigma scores and greater illness acceptance compared to other treatments.The correlation between stigma and acceptance of illness is positive. Authors suggest that acceptance of illness should not always be perceived as having a positive effect. It is strongly recommended to incorporate stigma screening into the management plan of patients requiring both insulin and oral antidiabetic drugs. A comprehensive evaluation of patients with diabetes must account for both stigma and illness acceptance concurrently.