Malocclusions are a high-frequency pathology that requires a treatment that considers the specific characteristics of each patient. The objective of this study was to relate the facial biotype with the transverse diameters of the jaws. This non-experimental, descriptive, and transversal design considers 58 registers of patients aged 8 to 15 years old. The evaluation of the facial biotype was performed by Jarabak cephalometric analysis, and the evaluation of transverse diameters included the intermolar and intercanine diameters proposed by Moyers and McNamara. Data analysis was performed in Excel and SPSS programs and included the Chi-square statistical test, which is appropriate to establish the relationship between the qualitative variables of this research. The results showed that the predominant facial biotype was the mesofacial (43.1%), followed by the dolichofacial (39.6%) and the brachyfacial (17.2%). The upper intercanine diameter was increased in 65.5% of cases and the lower by 75.9%, and only 32.8% of the upper intercanine widths and 15.5% of the lower intercanine widths were within normal limits. In the case of the intermolar diameter, it was increased in 100% of the cases, becoming a constant. In conclusion, there is no statistically significant relationship between facial biotype and the upper and lower inter-canine diameters according to the statistical test (p-value was 0.056 and 0.683, respectively). Therefore, one of the variables is not a good reference for the establishment of the other so the orthodontists should perform individualized evaluations in all cases.