A BSTRACT Background: Diabetes mellitus [DM] is the most prevalent disease that affects modern human life in Saudi Arabia. People with DM must have a comprehensive understanding of the nature, risk factors, complications, and treatment methods to mitigate complications. Aim: The aim of the study is to assess diabetic patient awareness of complications and their effect on treatment compliance in the Asir region of Saudi Arabia. A cross-sectional study was conducted targeting available diabetic patients in the Asir region, Saudi Arabia. Patients aged 18 years or more living in the Asir region with type 1 or type 2 diabetes were included. Data were collected from eligible patients using a pre-structured electronic questionnaire. The tool covered the following data: patients’ sociodemographic data, patients’ diabetes duration, patients’ compliance with medical care and treatment, patients’ awareness regarding diabetes-related complications, and patients’ experienced complications. The questionnaire was uploaded online using social media platforms by researchers. Results: A total of 466 diabetic patients fulfilling the inclusion criteria completed the study questionnaire. Patients’ age ranged from 18 to more than 50 years old, with a mean age of 38.9 ± 12.6 years old, Of the 279 patients, 59.9% were males. 143 [30.7%] patients reported measuring HbA1c every three months. 363 [77.9%] reported having a blood glucose meter at home, but only 205 [44%] reported having a good concern to measure their blood sugar and 211 [45.3%] had good diabetic control, while 124 [26.6%] reported excellent control. Of those, 218 [46.8%] patients had good awareness levels regarding diabetes-related complications, while 248 [53.2%] had poor awareness levels. Conclusions: Our study showed that diabetic patients living in Asir region had an average awareness level regarding diabetes-related complications, especially newly diagnosed, young people. Interestingly, diabetic patients showed good-to-excellent adherence to medical care and medications.