Introduction: At present there is little reference to the configuration of dental arches in Latin American populations and have been described many forms and variations for these arcs are derived especially from Caucasian patients. Objetive: Describe the shape and size of the dental arches three Colombian populations (mestizo, indigenous, Afro-descendant) under occlusion Normo. Materials and methods: A cross over 184 models of study according to their racial characteristics and population were divided into 3 groups, 66 Indians, 70 and 48 mestizos African descent aged between 11 and 41 years old. The variables studied were intercanine width, intermolar distance, above the arc length, circumference of upper and lower arch. The photocopies of study models were scanned and subsequently determine the shape of the arc by three observers. Results: The predominant form in the three races is the oval. There is low correlation between maxillary and mandibular arch in the same individual. There was a significant relationship between the arc-shaped square top and Indian ethnicity. There was significant difference in the upper intercanine width between arch forms. Conclusions: The ovoid shaped arched is the most prevalent in all ethnic groups, a significant difference was found in the intercanine width between the arch shapes for the upper arch. There was a significant relationship between indigenous ethnicity and the shape of a square upper arch.