Evidence that facial width-to-height ratio (FWHR) is a sexually dimorphic morphological measure is mixed. Research has also linked FWHR with aggression and other behavioral tendencies, at least in men. Again, other research has found no such relationship. Here, I tested for both possible relationships using a sample of 2,075 male and 1,406 female athletes from the Glasgow 2014 Commonwealth Games. Men showed significantly greater FWHRs than women, but this difference could be attributed to differences in body size. In addition, I found greater FWHRs in men who competed in sports involving physical contact and those stereotyped as more masculine. Again, these results could be attributed to differences in body size between categories. For women, no differences in FWHR were found regarding the amount of contact involved in a sport and how that sport was stereotyped. Finally, the FWHRs of athletes showed no relationship with the amount of aggression and related traits that were judged as required for success in those sports, although FWHRs did correlate with perceived endurance demands in women. Therefore, in a large sample of athletes, the sex difference in FWHR could be attributed to body size, and little support was found for the predicted links between this facial measure and behavior.