Potentially fatal arrhythmias add to the mental health challenges of adolescence. This systematic review sought to summarise current knowledge regarding the mental health of adolescents and pre-adolescents diagnosed with inherited arrhythmia syndromes. Searches combining psychological problems with inherited cardiac arrhythmia diagnoses identified 16 studies with paediatric (<18 years) inherited arrhythmia patients. All studies were cross-sectional; 8/16 required an implantable cardioverter defibrillator. Methods were quantitative (n=11), qualitative (n=4), or mixed (n=1), with 14–100% of participants having an inherited arrhythmia syndrome. Mean/median age in 13/16 studies was 12–16 years. Patients and parents reported lower quality of life, particularly in relation to physical function, social relationships, restriction of peer activities, bodily pain, and mental and emotional health. Self-perceptions and behaviour were similar to healthy populations. Rates of anxiety and depression (15–33% of these patients) were not increased in these studies where patients were assessed 2+ years after diagnosis. Higher mental health risk occurred among patients who have a diagnosed sibling, those with cardiomyopathy, and those who report decreased quality of life. Mental health research among youth with inherited arrhythmias is extremely limited and of low quality. Data, primarily from patients 2–4 years after diagnosis or treatment with an implantable cardioverter defibrillator, indicate that quality of life may be decreased and 15–33% experience mental health issues. Future research is required to examine the mental health and quality of life of paediatric patients with inherited arrhythmia syndromes, whether or not they have an implantable cardioverter defibrillator, from time of diagnosis.