Context: Arterial blood gases sampling is part of everyday nurses’ practice in the care of children admitted to the pediatric intensive care unit, particularly for those receiving respiratory support. Aim: To evaluate the effect of video-assisted teaching intervention on nurses’ knowledge and practice regarding arterial blood gases sampling for ventilated children at pediatric intensive care units. Methods: A quasi-experimental research design was utilized to conduct the current study. Settings: The study was conducted at Pediatric Intensive Care Units (PICUs) of Benha University Hospital and Benha Specialized Pediatric Hospital at Benha city. Sampling: A convenient sample of (70) nurses working at the above-mentioned settings were included in this study regardless of their personal characteristics. Tools of data collection: Two tools used, Tool 1: A structured interviewing questionnaire designed to assess nurses’ personal characteristics, personal data of the studied children, and nurses' knowledge regarding arterial blood gases sampling. Tool 2: An observation checklist to assess nurses' practice regarding arterial blood gases sampling. Results: There was a significant improvement in nurses’ total knowledge and practice regarding arterial blood gases sampling after video-assisted teaching intervention. Conclusion: It can be concluded that video-assisted teaching intervention had a positive effect on the improvement of nurses' knowledge and practice level, which indicates that the video-assisted teaching intervention is an effective method. Recommendation: The study recommended that applying the video-assisted teaching intervention for nurses caring for ventilated children helps to promote and update their knowledge and ensure competent practice.