Background: Clinical research examining the use of mineral trioxide aggregate (MTA) as an apical barrier material are limited, and no studies have so far examined the clinical performance of BioAggregate as apical barrier material in nonvital immature teeth. Aim: This study was aimed to provide a comparative evaluation of the clinical and radiographic success of MTA and BioAggregate as an apical barrier material in children with traumatized nonvital, immature permanent maxillary incisors. Subjects and Methods: A total of 26 maxillary incisor teeth in 20 children aged 7u11 were chosen for this study. Teeth were randomly divided into two groups according to the material to be applied, and the apical barrier was performed. Following treatment, for 24-month, teeth were clinically and radiographically evaluated once every 3- and 6-month, respectively. Results: All teeth treated with MTA and BioAggregate were clinically and radiographically successful throughout the 24-month follow-up period. Conclusions: Similar success was achieved in the apical barrier that using BioAggregate and MTA. BioAggregate would be considered suitable materials for apical barrier technique and can be used as an alternative to MTA.