<p><strong><em>Background: </em></strong><em>Knowing the important relation between knowledge and skill is important because it reflexes the action that nurses do to save people life. </em></p><p><strong><em>Objective: </em></strong><em>This research aimed </em><em>to determine the relationship between the nurse's knowledge level and their performance on c</em><em>ardiopulmonary resuscitation</em><em> in critical and emergency care unit. </em></p><p><strong><em>Method</em></strong><em>: The study was </em><em>quantitative descriptive with the cross-sectional design used sequential sampling with 30 nurses in critical and emergency care unit. The data were analyzed using </em><em>the Fisher Exact Test</em><em>. Data was taken from questioner and observational assessment using a standard operating procedure which was developed by a hospital. </em><em></em></p><p><strong><em>Results</em></strong><em>: The results of this study found that there were 63.3% respondents which all of them had poor knowledge also poor performance on doing c</em><em>ardiopulmonary resuscitation</em><em>. </em><em></em></p><p><strong><em>Conclusion</em></strong><em>: T</em><em>here is a relation between </em><em>nurse’s knowledge level and the nurse’s performance on undertaking c</em><em>ardiopulmonary resuscitation</em><em>. The more knowledge they have the better performance they have on c</em><em>ardiopulmonary resuscitation</em><em>. Routine training and evaluation may be useful to increase nurses’ knowledge and skills.</em><em></em></p>