OBJECTIVE: To verify the influence of sex (male, female) on facial anthropometric measurements in children aged between 3 and 5 years. CASE REPORT: This cross-sectional study involved 93 children with deciduous dentition and complete eruption of the first 4 deciduous molars; the children were selected using a consecutive convenience sample. Each child underwent an anthropometric evaluation of their face based on the MBGR protocol (Genaro et al., 2009). The following were analyzed: the middle third of the face (glabellar sub-nasal), the lower third of the face (sub-nasal gnathion), face height (glabella to gnathion; the sum of the middle and lower thirds), the outer corner of the right eye to the right lip commissure, the outer corner of the left eye to the left lip commissure, the upper lip (sub-nasal to the lowest point of the upper lip), and the lower lip (the uppermost point of the lower lip to the gnathion). The anthropometric measurements were performed by the same speech therapist who was experienced in using the measuring instrument. The level of significance was p < 0.05. Statistical differences in measures of the lower lip (p < 0.001), upper lip (p = 0.001), lower third of the face (p < 0.001), and the height of the face (p = 0.003) were observed with all being greater in the male children. CONCLUSION: Measures related to the lower third of the face were greater among the male compared with the female children. The literature suggests that there is sexual dimorphism in human children, and our study agrees with this contention since the measurements obtained in this analysis were larger among the male compared with the female children.