Introduction: Life quality is regarded as one of the important concepts in diabetic mellitus as a chronic disease, which produces extensive effects on the social and individual performance. Regarding the short-term and long- term complications as well as expensive costs of this disease, the present study aimed to determine the life quality of these patients compared to non-diabetic people and ultimately, a structural model was presented.

methods: This analytical study was carried out on 250 diabetic and 250 non-diabetic patients in Yazd. The standard life quality questionnaire (whoqol-bref) was utilized as the data collection tool containing a total of 26 questions and 4 domains of physical health, mental health, social health and environmental health. The study data were analyzed using SPSS software (ver.16) and Amos(21).

Results: The study results demonstrated a significant difference between life quality of diabetic patients and healthy subjects (p<0.001), and the mean score of all the different domains of questionnaire proved to be lower in patients than healthy subjects. Path coefficients in the structural equation model proved to be significant (p<0.001). The path coefficient between the environmental and social health with the mental health was 0.62 and 0.76 respectively., and, it was reported 0.96 between the physical health and mental health Eighty-six percent of changes of the physical health variable was explained by the mental health variable and 96% of changes of the mental health variable was explained by the social and environmental health.

Conclusion: The study findings revealed diabetes as a chronic disease that can severely affect the patients’ life quality. Every type of attempt in structural models of predicting physical health and life quality plays a meaningful role in alleviating these patients’ problems.