Abstract Background Increasingly, the emergency department (ED) is a vital safety net for children and adolescents with mental health concerns seeking crisis care. Evaluating patient and parent/caregiver experience and satisfaction with care is essential to improve the quality of mental health services provided. Objectives The primary objective was to evaluate total satisfaction with the delivery of ED mental health care in two paediatric EDs in Alberta, Canada (Stollery Children's Hospital and Alberta Children's Hospital). Secondary objectives included exploring aspects of ED mental health care (staff interpersonal skills, confidentiality/privacy, and patient-reported outcomes of care) associations with general satisfaction, patient and ED visit characteristic associations with total satisfaction score, and care experience themes. Design/Methods We enrolled patients <18 years of age presenting with a mental health concern—e.g., anxiety, disruptive behaviour, self-harm, depression, situational crisis—over a 12-month period (February 1, 2020—January 31, 2021). Satisfaction data were collected using the Service Satisfaction Scale, which includes quantitative and qualitative data on aspects of ED mental health care. ED visit (length of stay, mental health and psychiatry consultations, hospital admission) and patient (discharge diagnoses, age, sex) data were collected. We evaluated associations of general satisfaction with ED mental health care using Pearson’s correlation coefficient tests, and associations between total satisfaction score with patient and ED visit characteristics using multivariable regression analyses. Inductive thematic analysis of qualitative feedback identified satisfaction and patient experience themes. Results 646 participants were enrolled with most being Caucasian (71.2%; 460/646) and female (56.3%; 364/646); the median age was 13 years (IQR, 11-15 years). The most common discharge diagnosis was anxiety or stress-related disorders (39.5%; 245/620). Parents/caregivers and adolescents were most satisfied with confidentiality and respect in the ED and least satisfied with how the ED services helped reduce symptoms and/or problems. Greater satisfaction was reported for parents/caregivers whose child received care at Alberta Children’s Hospital (p=0.003). General satisfaction was strongly associated with the perceived amount of help received in the ED (r=0.85). ED visit characteristics associated with total satisfaction score included an evaluation by a mental health team member (p=0.004) and psychiatrist consultation (p=0.05). Written comments demonstrated satisfaction with ED provider attitudes and interpersonal skills and dissatisfaction with access to mental health and addictions care, wait time, and COVID-19. Conclusion The results reflect the need to improve the satisfaction with ED mental health care delivery, with a particular focus on enhancing access to care by appropriate mental health providers.