Background: In the State of Mexico there are no investigations that provide information for decision-making and administration of resources related to the care of externally-caused injuries (ECI). Objective: To describe ECIs seen in an emergency department over a 5-year period. Method: A retrospective study was designed with patients admitted to emergency department (2010)(2011)(2012)(2013)(2014)(2015) with ECI diagnosis. Descriptive and cluster analyses were performed. Results: At the emergency department, 16.59% of emergency care was related to ECI. A total of 16,567 patients of 14 to 99 years of age (average = 37.7; SD = 17.28) were included; 69.2% were males. ECIs occurred mainly in public places (26.3%) and at home (23.7%). The main causes were aggression outside the home (32.7%), on average at 34 years of age, falls (25%) on average at 45 years, and motor vehicle accidents (9.7%) on average at 33 years. The cluster analysis identified four groups: aggression outside the home 32.7% (5,417), traumatic contacts, 26.30% (4,363), road traffic accidents 15.9% (2,640) and falls 25% (4,147). Conclusions: Motor vehicle accident-related ECIs showed the most severe consequences.