This study aimed to assess mental health, family burden, and quality of life (PQoL) in parents of children with persistent congenital hyperinsulinism (CHI). Forty-eight individual CHI parents (75% female) completed self-reported questionnaires and screening tools for anxiety (GAD-7), depression (PHQ-8), PQoL (ULQIE), and family burden (FaBeL). Additional data on sociodemographics, social support, and child- and disease-related data were recorded. 29.8% of parents showed major depressive symptoms and 38.3% had a probable general anxiety disorder, including 20.8% who had both. The family burden was moderate and assessment of PQoL yielded average scores. Neurological impairment in an affected child (p = .002 and p < .001, respectively) and lower working hours (p = .001 and p = .012, respectively) were the strongest predictors of worse GAD-7 and PHQ-8 scores. Furthermore, lower working hours (p = .012) and comorbidities in the affected child (p = .007) were significantly associated with lower PQoL. Mothers had worse GAD-7 scores (p = .006) and lower PQoL (p = .035) than fathers. Indication of sleep disturbance was associated with worse PHQ-8 scores (p = .003), higher family burden (p = .039), and reduced PQoL (p = .003). A higher number of caretakers besides parents was associated with decreased family burden (p = .019), improved PQoL (p < .001), and lower scores for anxiety (p = .016) and depressive (p = .021) symptoms. Conclusion: Symptoms of depression and anxiety are alarmingly prevalent in parents of children with CHI. Psychological screening of parents should be initiated to ensure early identification of psychological strains and psychosocial support should be offered as needed. A good support network and regular work activities can improve parental mental health and well-being.What is Known:• Psychosocial strains and reduced quality of life are common in parents of chronically ill children.What is New:• In this first study evaluating mental health, family burden, and quality of life in parents of children with congenital hyperinsulinism (CHI), symptoms of depression and anxiety were alarmingly prevalent.• Parents of children with CHI should receive regular psychological screening and psychosocial support should be offered as needed. A good support network and regular work activities can improve parental mental health and well-being.