Introduction: The purpose of this study is to investigate patterns of emergency department (ED) utilization relating to injured FR compared to NR. Material & Methods: This is a retrospective cohort study of two urban academic EDs. We included all patients visiting ED due to injury from year 2010 to 2014. FRs are defined if the second part of Social Identification Number starts with 5 to 8. Injured patients are extracted from the ED ICD-10 code starting with‘ S’or‘ T’. All ICD-10 codes related to injury are transformed to EMR-AIS and are defined as‘ severe injury’(SI) if EMR-AIS is 3 to 5. Results: Total 524,456 patients from year 2010 to 2014, 126,578 patients visited ED due to injury and 66,919 patients were categorized as SI. From SI patients, 2,565 patients (3.8%) were FRs. In FRs, proportion of health insurance was 52.5% (NR 86.8%) and those with no insurance were 32.9% (NR 1.0%). 21.2% of FR was injured due to violence (6.3% in NR) and 1.7% were injured from self-harm including suicide attempt (0.9% in NR). From SI patients visiting ED, 11.9% of FR was admitted to hospital (NR 12.7%) and 8.6% were transferred to other hospitals (NR 3.7%). Conclusion: From this cohort study, higher proportion of FR has no insurance and visited ED due to violence and self-harm attempt. This may have affected higher transfer rate of FR at ED. Further data collection and investigation is needed.