Background: The chest tube is a common therapeutic postoperative procedure used in cardiothoracic and respiratory care. Patients with hemothoraces, effusions, or pneumothoraces may benefit from a chest tube as a life-saving procedure. Nonetheless, it is linked to a high rate of morbidity and death. So, the study aimed to determine the effect of educational guidelines application on nurses' performance in caring for patients undergoing chest tubes. Design: A quasi-experimental design was used to accomplish this study (pre/post-test).  Setting: The research was conducted at the chest intensive care unit which is affiliated to Sohag University Hospital.  Sample: The study subjects included a convenient sample of 50 of all available nurses working in the previous setting. Tools of data collection: Tool I: Nurse`s knowledge questionnaire sheet and Tool II: Nurse`s practice observation checklist sheet. Results: The study result revealed that there was a highly statistically significant positive relation between total knowledge scores and total practice scores of the studied nurse's pre and post-educational guidelines implementation regarding chest tubes. Conclusion: It was concluded that educational guidelines had a positive effect on improving nurses' knowledge and practice regarding chest tubes. Recommendations: Continuous educational programs and in-service training programs about chest tubes should be provided to nurses to upgrade nurses knowledge and skills.