Aim: In this study, it was aimed to test the design of the Diabetes Mellitus simulation method prepared in accordance with ST-IX prepared by The International Nursing Association for Clinical Simulation and Learning. Material and method: This study is planned as cross-sectional. The study was completed with 169 students at Internal Diseases Nursing course at Public University in Turkey. Their opinions and achievement scores were used to evaluate the research results. Results: As the Diabetes Mellitus simulation scores of the students increased, the application note and the end-of-semester grade rose. The students expressed their opinions about simulation training with 'I was worried before the internship', 'I learned to interpret the disease' expressions. Conclusion: The simulation, prepared and put into practice for the management of Diabetes Mellitus in accordance with the stages of EİUS:ST-IX, increased practice and end of term grades of students and according to students’ statements, it increased their self confidences, decreased their preclinical concerns and is effective on learning.