© 2021Background & aims: There are studies in the literature that consider only the opinions of older adults about food service or only the status of meeting dietary needs to evaluate the quality of food services. However, evaluating both satisfaction (residents' perspective) and nutritional adequacy (experts' perspective) together is important for ensuring adequate food intake and meeting dietary requirements. This study aimed to evaluate the quality of nursing home food service from both perspectives and to detect its effects on older adults’ nutritional status. Methods: A cross-sectional study was conducted on 101 older adults. Satisfaction with the food service and nutritional status was assessed using a questionnaire and the Mini Nutritional Assessment Short Form. Results: The 28-days menu had higher energy for females, lower protein for males, higher fat and sodium for both genders, and inadequate micronutrient (vitamin B6, folic acid, vitamin B12, potassium, calcium, magnesium, etc.) contents than recommended. Older adults were 65.1% satisfied with food service, and dissatisfaction was associated with a decrease of 8.42%, 6.85%, and 6.25% in meeting their energy, protein, and fiber requirements, respectively, and an increase of almost 20 times in malnutrition risk. Conclusion: Our findings shed light on the importance of food service quality in nursing homes and of evaluating the satisfaction of residents, as well as the nutritional adequacy of menus.