Abstract Rationale, aims, and objectives: Cardiac failure is one of the most common chronic diseases with high rate of morbidity and mortality. Fatigue and decreased ability to perform daily activities are of the most common complications of this disease. The purpose of this study was to determine effect of care plan based on Roy adaptation model on fatigue and daily activities in patients with heart failure. Methods: This clinical trial was performed on 60 heart failure patients admitted in two educational hospitals supervised by the Kerman University of Medical Sciences in 2019. Sample was randomly assigned into two intervention and control groups. The intervention group received the care plan through a face to face and group training program in 6 sessions at one month. Interval followed by a follow-up period for 4 weeks later, while the control group only received the regular services from hospital. Fatigue level was calculated based on piper fatigue scale and daily activities were calculated by Barthes scale. Results: finding indicated there was a significant difference between the two groups control and intervention after the intervention. Result showed that the intervention group had significantly lower mean scores in fatigue and higher mean scores in daily activities compared to the control group after intervention P ≤ .05. There was significant relationship between fatigue and daily activities of life with frequency of hospitalization and duration of disease in both groups P ≤ .05. Conclusion: Implementation of Roy model based education program as a low-cost, effective, and non-aggressive nursing intervention can affect fatigue and improve the ability to perform daily activities in patients with heart failure.