Introduction: Caring for patients with chronic disorders can lead to different problems for caregivers in physical, psychological, social, family, and financial domains. High levels of burden of care can make caregivers vulnerable to physical and psychological conditions and influence their quality of life. Therefore, the goal of the present study was to estimate the overall percentage of burden of care in caregivers of Iranian patients with chronic disorders. Methods: A total of 25 articles published from inception to February 2019 were reviewed. Search for articles was conducted in international (Scopus, Web of Science, and PubMed) and domestic (Scientific Information Database (SID) and MagIran) databases, using the following keywords: "Caregiver," "Burden," and "Iran," and their possible combinations. The data were analyzed using the meta-analysis method and the random effects model. All the analyses were performed using STATA, version 14. Results: The overall percentage of burden of care in caregivers of Iranian patients with chronic disorders was 53.28% (95% CI: 46.13-60.43). The highest percentage of burden of care was related to dialysis (62.75; 95% CI: 56.11-69.38), mental disorders (58.69; 95% CI: 49.70-67.69), and Alzheimer's disease (57.07; 95% CI: 46.23-67.92), respectively; and the lowest percentage of burden of care was related to diabetes (34.92; 95% CI: 18.01-51.82). Conclusions: Caregivers of Iranian patients with chronic disorders experience high levels of burden of care, especially those caring for patients undergoing dialysis, patients with mental disorders, and patients with Alzheimer's disease. Therefore, necessary measures need to be taken by Iranian health care officials to reduce burden of care in caregivers.