Aim:The purpose of this study was toevaluate the efficiency of polyethylene fiber reinforced composite versus conventional band and loop space maintainer in pediatric dental clinics. Methods:This study, carried on fifty children with an age range of 5-8 years old, selected fromthe outpatient Pediatric Dental Clinic, Faculty of Dentistry, MansouraUniversity. Children were selected with bilateral premature loss of first primary molarsor second primary molars.The polyethylene fiber reinforced composite space maintainer was placed on one side while the band and loop space maintainer was placed on the other side. Children were followed up for 3, 6 and 12 months. Results:At 3 months follow up period, the polyethylene fiber reinforced composite space maintainers failure and success rate accounts for 8% and 92% respectively, while the band and loop space maintainer failure and success rates accounts for 6% and 94% respectively. At six months follow up period, the polyethylene fiber reinforced composite space maintainers failure and success rate accounts for 24% and 76% respectively, while the band and loop space maintainer failure and success rates accounts for14% and  86% respectively. At twelve months follow up period, the polyethylene fiber reinforced composite space maintainers failure and success rates accounts for 58% and 42%  respectively, while the band and loop space maintainer failure and success rate accounts for 28% and 72% respectively. Conclusion: The band and loop space maintainer is more efficient for a longer period than the polyethylene fiber reinforced composite space maintainer. The polyethylene fiber reinforced composite space maintainer could beaccepted as successful space maintainer only for short  periods.