Goals of work Allogeneic pediatric stem cell transplantation (SCT) is a very intensive treatment with a high mortality and morbidity. The objectives of this study were to assess the (1) self-and proxy-reported health-related quality of life (HRQoL) compared to a norm group, (2) levels of parenting stress compared to a norm group, (3) differences in HRQoL and parenting stress pre-and post-SCT, and (4) effect of child age and parenting stress on selfand proxy-reported HRQoL pre-and post-SCT. Materials and methods Pre-and on average 10 months post-SCT, 21 children and adolescents and their parent(s) completed questionnaires on HRQoL and the mothers completed a measure of parenting stress. Main results Post-SCT, home functioning, physical functioning, and total HRQoL scores were lower than the norm group. We found stable HRQoL scores over time with the exception of the domain home functioning, which was rated lower post-SCT than pre-SCT. Parents reported lower HRQoL scores than the children pre-and post-SCT and younger children experienced better HRQoL than older children. Parenting stress was higher post-SCT than pre-SCT and high levels of parenting stress were predictive of poor parental ratings of child HRQoL post-SCT. Conclusions Ongoing psychosocial assessment post-SCT is necessary to target children with a lowered HRQoL and parents who experience elevated parenting stress who may be in greater need of more supportive care.