Background: Critically ill children often connected with many tubes and lines. Physical restrain routinely implemented in critical care unit to reduce child's self-injury and improve safety. Therefore, the current study conducted to improve pediatric critical care nurses' knowledge and practice regarding restraint application and children's outcomes. Subjects and Method: Design: A quasi-experimental non-randomized intervention design pre-posttest one-group was utilized. Subjects: A convenience sample of 43 nurses working in Pediatric Intensive Care Units (PICUs) at Mansoura University Children's Hospital (MUCH) affiliated to Mansoura University, Egypt was recruited in the present study. Results: The current study showed that nurses take the decision of restrain without parents' permission or participation. Sedation is the alternative to physical restrain in PICUs as reported by nurses. The most common health problem among children is respiratory problem and the prevalence of restraint related complications reduced post intervention phase compared to baseline data. In addition, there is an improvement in the total level of knowledge. Reported and observed practices post intervention also, were improved as compared to pre intervention with statistically significant differences. Conclusion: The current study concluded that, the training program application is the best approach to improve knowledge and practices regarding using of physical restraint and reducing restraint related complications among children. Recommendation: Documentation system that includes physical and chemical restraint assessment and evaluation and restraint related complication documentation is mandatory.