Background: Celiac disease (CD) is a chronic, systemic immune disorder that can affect one’s quality of life. Objectives: The aim of this study was to explore the key performance indicators (KPIs) related to the quality of life of patients with CD admitted to the Celiac Association of Bouali Hospital in Zahedan. Methods: This descriptive-analytical study was performed on 60 patients with CD who referred to the Celiac Association of Bouali Hospital in Zahedan in 2018. Data collection tools included a demographic questionnaire (age, gender, marital status, duration of illness, education, ethnicity, economic status, occupation, breastfeeding history, family history of CD, as well as vitamin D and iron supplementation) and the Quality of Life Questionnaire for patients with CD. Data were analyzed in SPSS 21 using descriptive statistics. All values less than 0.05 were considered statistically significant. Results: Sixty participants completed the study, 66.7% of whom were female, 76.7% were married, and 85.3% reported a family history of CD. The total score of patients’ quality of life was 81.66 ± 18.33, and the lowest score of quality of life was associated with patients’ concerns (51.81 ± 3.85). The findings also showed that, among various KPIs, vitamin D had a particularly significant relationship with patients’ quality of life. Conclusions: There was a significant relationship between the quality of life and vitamin D supplementation in the participants. Besides, considering the effect of physical health on improving the quality of life and the chronic nature of CD, it is necessary to enhance the quality of life of these individuals by raising their awareness about micronutrient intakes while respecting their dietary restrictions.