Objective: The aim for this study was to explore the proportion of patients with a Substance Use Disorder (SUD), their proportion of overall admissions, and their psychosocial histories at a regional child and adolescent inpatient psychiatric unit. Methods: A retrospective chart review was conducted on all admissions of patients with a SUD. Abstracted patient data included demographic information, diagnoses, psychosocial histories, living situation at the time of admission, legal involvement and charges, whether an alternate level of care was needed, and discharge plans. Results: From September 2018 to February 2020, of the 540 patients admitted, 126 (23.3%) had a SUD recorded in their charts and accounted for 34.6% of the total number of admissions. Their mean age was 15.85 (SD 1.10; range 13 to 18) years, and most were identified as female (n=81; 64%), which is consistent with the number of female patients admitted during the study period (n=366 female of 540 admitted; X2=0.56, p= 0.45). Common psychiatric diagnoses included mood, trauma, and stressor-related and anxiety disorders. Most patients (124; 98.4%) had a history of psychosocial adversity, 90 (71.4%) patients had a parent with a mental illness or a SUD, 55 (44%) reported being bullied, 54 (43%) reported being sexually assaulted and several (n=41;33%) had experienced precarious living situations. Conclusion: Adolescent inpatients with a SUD were also managing a complex array of clinical and psychosocial challenges. Upon discharge from the hospital, some patients were placed on waitlists, and many patients were referred to specialized treatment far from home, highlighting the need for additional, comprehensive programs for SUD and the constellation of psychosocial problems associated with these disorders.