Background: Heart failure (HF) is a chronic condition that affects a significant number of patients worldwide, requiring specialized management. Nurses have a great role in caring of such group of patients. Aim: The study aimed to investigate the effect of intervention program on nurses caring of patients with heart failure, at the Cardiac Care Unit (CCU). Method: A quasi-experimental research design was utilized in this study. The study included 30 nurses working at the Cardiac Care Unit. For data collection, two different tools were used. Tool I: A Structured interview Knowledge Questionnaire; Tool II: Nurses' Observational Checklist. Results: The study results showed significant differences pre and post implementation of the intervention program regarding nurses' level of knowledge and practice compared to their pre-intervention levels with (p = 0.00). Conclusion, the results of this study concluded that the implementation of the intervention program revealed a significant positive improvement of nurses' knowledge and practice level regarding care of patients with heart failure. Recommendation, conducting in-service training programs for nurses caring patients with heart failure is recommended to keep them up to date with the latest information and evidence-based practices that related to care of patients with HF.