Background: Acute coronary syndrome (ACS) refers to a group of conditions due to decreased blood flow in the coronary arteries such that part of the heart muscle is unable to function properly or dies. Aim: To evaluate the effect of implementing an educational program on knowledge and practices of critical care nurses regarding acute coronary syndrome. Sampling: convenient samples of 30 nurses recruited from coronary and Emergency care unit at Manfalout's Reproductive Health Hospital. Research design: quasi-experimental research design (one-group pretest-posttest design) was used for implementation this study. Result: Most of nurses (66.7%) had unsatisfactory level of knowledge regarding acute coronary syndrome, Most of nurses (36.7%) had unsatisfactory level of practice regarding acute coronary syndrome and no significant statistical relation between knowledge and practice level of studied nurses. Data collection: Data were collected in six months. Conclusion: empowerment of emergency nurses' knowledge and practices would have a positive impact upon their knowledge and practice related to acute coronary syndrome. Recommendations: All nurses should be equipped with the necessary knowledge and practice regarding acute coronary syndrome.