Introduction: Parental presence during invasive procedures is important in family-centered-care. Family-centered-care is a basic principle of pediatric nursing. Methods: This randomized controlled trial included data from 111 cases in the Pediatric Emergency Department of Istanbul University, Istanbul Medical Faculty, during October 2016-January 2017 (parental involvement group, n = 40; parental presence group, n = 40; parental absence group, n = 31). Information form, State-Trait Anxiety Inventory, State-Trait Anxiety Inventory for Children and Visual Analogue Scale were used to collect data. Results: When children's pain levels before invasive procedures were compared, there was no significant difference between the groups (P > 0.05). Significant difference was found between pain levels of the groups during the process (P < 0.001). It was found that the pain levels of the children in the parental absence group (6.00 +/- 2.88) were significantly higher than those in the parental involvement group (3.15 +/- 2.79) and the parental presence group (3.70 +/- 2.92) (P < 0.05). There was a weak, positive, and significant relationship between parents' trait anxiety levels and the preprocedural pain and trait anxiety levels of children in all groups (P< 0.05). Discussion: Parental involvement is effective in reducing the pain felt during invasive procedures. Moreover, anxiety levels of children during the procedure were not affected in all groups; however, the children of parents with high trait anxiety levels had higher preprocedural pain and trait anxiety levels.