Objective Treatment of pediatric growth hormone deficiency (pGHD) with daily injection of recombinant human growth hormone (somatropin) aims to increase height velocity and improve health-related quality of life (HRQoL). The Quality of Life in Short Stature Youth (QoLISSY) questionnaire was administered in a phase 3 clinical trial that evaluated efficacy and safety of once-weekly somatrogon versus once-daily somatropin in children with pGHD (ClinicalTrials.gov no NCT02968004). Methods Treatment-naïve prepubertal children with pGHD received once-weekly somatrogon or once-daily somatropin for 12 months. The QoLISSY core module (physical/social/emotional subscales) was administered at baseline and 12 months after treatment initiation. QoLISSY-Parent was completed by parents/caregivers of children <7 years old and some parents/caregivers of children ≥7 years old; children ≥7 years old self-completed QoLISSY-Child. Results Baseline characteristics were similar between treatment groups (N = 117). Among children <7 years old, QoLISSY-Parent total and subscale scores showed similarly improved HRQoL at 12 months relative to baseline in both treatment groups. Self-reported QoLISSY-Child total and subscale scores in children ≥7 years old indicated HRQoL improvements at 12 months that were numerically better with somatrogon than somatropin (similar results with QoLISSY-Parent in this age group). At both time points, children reported better HRQoL than perceived by their parents/caregivers. Conclusion Treatment for 12 months with once-weekly somatrogon or once-daily somatropin resulted in comparable improvements in HRQoL among children with pGHD. Lower HRQoL perceived by parents/caregivers possibly reflect children’s tendency to emphasize adaptation. These results suggest that evaluation of HRQoL could help support treatment decisions in children with pGHD treated with growth hormone.