Background: Pediatric COVID-19 vaccine hesitancy hinders the establishment of immune barrier in children. Psychological flexibility may be a key contributing factor to pediatric COVID-19 vaccine hesitancy, and self-efficacy and coping style play an important role in the relationship, but the underlying mechanisms remain unknown.Methods: A cross-sectional study was conducted on parents from June 2021 to July 2021. A total of 382 parents were recruited for an online-investigation. Serial mediation models were used to examine whether self-efficacy and coping style mediated in (...) the psychological flexibility-pediatric COVID-19 vaccine hesitancy linkage.Result: Psychological flexibility was negatively related to pediatric COVID-19 vaccine hesitancy. Coping styles rather than self-efficacy played a mediating role independently. Serial mediation analyses indicated that self-efficacy and coping style co-play a serial mediating role in the association of psychological flexibility and pediatric COVID-19 vaccine hesitancy.Conclusion: The present study showed that high psychological flexibility, high self-efficacy, and positive coping style were conducive to the lower pediatric COVID-19 vaccine hesitancy. (shrink)