Objective: To analyze the quality of life of people with type 2 diabetes mellitus in the three levels of the healthcare system. Method: A quantitative, cross-sectional and descriptive study carried out in primary, secondary and tertiary healthcare units with individuals in outpatient care. The validated Diabetes-39 instrument was used to evaluate quality of life. Results: The sample consisted of 53 people. There was a decreasing tendency in the quality of life impairment from the primary to the tertiary care levels. In the total sample, there were differences between domains of quality of life with the variables gender, insulin use and occupation, greater perception of quality of life impairment and disease severity in people with higher rates of glycated hemoglobin. Conclusion: Quality of life tends to worse as the disease worsens. The results suggest that quality of life is related to sociodemographic and clinical variables, therefore, these should be considered in the care.