Pressure ulcers are a common and highly relevant professional care issues in pediatric intensive care units. The aim of this study was to evaluate the effect of preventive bundle guidelines on nurses' knowledge and compliance regarding pressure ulcer among critically ill children at Pediatric intensive care unit. Research design: A quasi-experimental design was used. Settings: This study was conducted at the pediatric intensive care unit in Benha Specialized Pediatric Hospital. Sample: A Convenient sample of nurses (n=43) and purposive sample of critically ill children (n=70) were included from the above mentioned setting. Those children were divided equally into two groups (study and control). Tools of data collection: Three tools were used namely; a structured interviewing questionnaire format, pressure ulcer preventive bundle compliance checklist and Braden Q Risk Assessment Scale. Results: Most children in the study group were not at risk of pressure ulcer in the first and second week of admission as well as before discharge than children in the control group. Moreover, the results revealed that there was significant improvement in nurses' knowledge regarding pressure ulcer as well as their compliance with preventive bundle guideline after bundle implementation. Conclusion: The implementation of preventive bundle guidelines proved to be effective in improving nurses' knowledge and their compliance, with a positive impact on the incidence of pressure ulcer among critically ill children. Recommendation: Preventive bundle guidelines should be implemented in pediatric intensive care units to reduce the harm associated with hospital-acquired pressure ulcer.