Purpose: This study was conducted in order to evaluate the epidemiological characteristics of?children with fall-down injuries according to age groups and to analyze the major trauma groups that were treated at the emergency room (ER). Methods: Among 1,222 children under age 6 who were treated at the ER from January 2008 to December 2009, a retrospective study was conducted through examination of medical records. The children were classified by age into 3 groups: infant, toddler, and pre-schooler. In each group, the differences between the causative factors that led to the fall-down injuries were analyzed. Also, ISS (Injury Severity Score) score above 4 was classified as major trauma, and an ISS score 0-1 was classified as a minor trauma. The relationship between major trauma and age group was also analyzed. Results: Through an analysis of child fall-down injuries, men (56.6%), toddler (47.3%), head-related symptoms (72.9%), furniture-related traumas (80.2%), and falls from less than a 1-m height (69.9%) were found to be common factors. Furthermore, in radiological studies, fractures and brain hemorrhages accounted for 16.9% of major traumas, and simple skull fractures were the most common (21.4%). Distributed according to age group, the factors relevant to fall injuries were fall height and head-related symptoms for infants, accident site, fall height and head-related symptoms for toddlers, and accident site for pre-schoolers (p<0.05). Also, headrelated symptoms and fall height were independent factors of major trauma in all age groups. However, major traumas (17.3%) were related to dumped trauma, fall height and accident site (p<0.05). Conclusion: This study was mainly about head-related injuries, and toddler were most common victims. The relevant factors for the major trauma were falling height for infants, accident site and falling height for toddlers, and accident site, falling height for pre-schoolers.