Introduction: The tooth-bone discrepancy or dental crowding occurs in the early, mixed and permanent stage of the dentition and is considered a frequent characteristic in malocclusion. This condition generates other structural and functional alterations in the stomatognathic system that directly influence the shape and size of the dental arch. Objective: This research aimed to determine the relationship between the intermolar width and the tooth-bone discrepancy of the upper arch in children. Material and Methods: A convenience sample was constituted, made up of 57 plaster study models of children aged 6 to 10 years, who attended the orthodontic clinic of the Catholic University of Cuenca, from Cuenca, during the period from March to August 2018. The type of study was analytical, correlational, cross-sectional and retrospective, the collected data were analyzed by correlation coefficient and Pearson__ampersandsignrsquo;s R2. Results: The correlation coefficient of the variables was -0.046128083 and R__ampersandsignsup2; = 0.0021, showing that there was a null correlation between the intermolar width and the tooth-bone discrepancy of the upper arch. However, Pearson__ampersandsignrsquo;s R2 value expressed a maximum linear precision of 3% between the study variables. Conclusion: It is concluded that there is a null statistical relationship between the intermolar width and the bone-tooth discrepancy of the upper arch of the studied sample. A certain degree of continuity of the intermolar width was evidenced in values of 39-40 millimetres.