Objective. This study examined the relationship of multiple mild traumatic brain injuries (mTBIs) and psychological resilience to persistent post-concussion symptoms (PCS). Methods. Participants (N = 65), ages 8-18 years, who sustained multiple mTBIs (n = 24), a single mTBI (n = 22), or an orthopaedic injury (OI; n = 19) were recruited from a children’s hospital in Calgary, Alberta. Resilience was measured using the Connor-Davidson Resilience Scale (CD-RISC) and PCS were measured using the Post-Concussion Symptom Inventory (PCSI). Results. The multiple mTBI group and low psychological resilience were significant predictors of PCS. Conclusions. Sustaining multiple mTBIs may increase a child’s risk of persistent PCS; however, high psychological resilience may serve as a protective factor, regardless of the number of injuries a child sustains. Results of this study provide support for interventions aimed at increasing psychological resilience in order to improve outcomes for children suffering from persistent PCS after mTBI.