Background: Cardiothoracic surgery patients are exposed to a wide range of pain following tissue injury associated with surgery, so adequate pain control is a substantial factor in improving patients' outcomes. Non-pharmacological measures are an important part of pain management that is used by critical care nurses to increase the tolerance of experienced pain, decrease physical stress, reduce the feeling of weakness, and reduce the use of analgesics. The study aimed to assess nursing performance regarding non-pharmacological pain management for patients with cardiothoracic surgery at Zagazig University Hospitals. Research design: A descriptive design was used. Tools of data collection: An interview questionnaire and observational checklist were used to collect data. Study subjects: convenient sample of all available nurses (55) working in cardiothoracic surgery wards and open heart ICU at Zagazig University Hospitals. Results: Studied nurses' age ranged between 22-50 years old, 96.4% of them were females, 63.6% of studied nurses had a technical institute degree in nursing science, and 61.8% of studied nurses didn’t attend previous training courses about non-pharmacological pain management. Furthermore, 61.8% of studied nurses had unsatisfactory total knowledge and 67.3% had unsatisfactory total practice regarding non-pharmacological pain management. There was a positive statistically significant correlation of total nurses’ knowledge score with total practice score, nurses’ age, and nurses’ experience years in the nursing field and at the cardiothoracic surgery departments. Conclusion: Nurses had an unsatisfactory level of knowledge and practice regarding non-pharmacological pain management. Recommendation: Practical training programs and workshops are highly recommended to improve nursing performance regarding pain assessment and non-pharmacological pain management for patients with cardiothoracic surgery.