Introduction: In recent decades, there has been growing evidence suggesting that too little or too much sleep is associated with adverse health outcomes, including type 2 diabetes. There is a close association between diabetes and diabetic retinopathy (DR), so it is reasonable to assume that sleep may also have associations with DR. Objective: To explore the relationship between the perception of sleep quality and the degree of diabetic retinopathy in patients with type 2 Diabetes Mellitus treated at a 3rd level dophthalmological care service. Results: Significant correlations were found in: diastolic and systolic blood pressure (0.429), triglycerides and total cholesterol (0.707), glycosylated hemoglobin (HbA1c) and glycemia (0.561), Epworth sleepiness scale (ESS Score) and age (0.394) , ESS Score and weight (0.365), extended STOP questionnaire (Stop Bang) and age (0.317), Sto...