Sexual dimorphism of the distal humerus has been used for the development of morphometric sex estimation methods in human identification. In particular, visual assessment of the olecranon fossa, trochlear shape, and medial epicondyle angle are variably successful in differentiating females and males in African, Asian, and European groups. However, the influence of other factors on the distal humerus has yet to be fully explored. This study utilizes elliptical Fourier analysis (EFA) to examine the shape of these three features for evidence of sexual dimorphism and the effects of age-at-death, stature, and humeral measurements in 261 modern Thai individuals (f=116; m=145), 20-97 years of age. Left humeri were measured, photographed, traced, and analyzed in SHAPE v. 1.3 for EFA. Chi-square, ANOVA, and principal component results indicate sexual dimorphism in the olecranon fossa and trochlear extension shapes, both of which are correlated with epicondylar breadth. Trochlear extension was also found to be correlated with minimum midshaft diameter, vertical head diameter, and stature. The medial epicondyle was not correlated with any of the other factors examined, and age was not correlated with any of the shapes. High rates of intra- and interobserver error were found in the tracings of the three features. While future research should assess methods that better capture the medial epicondyle and improve reliability, features of the distal humerus are sexually dimorphic and somewhat affected by stature and/or body size.