Eating disorders (EDs) affect men at higher rates than previously estimated, with many traditional ED measures likely underestimating the prevalence of eating and exercise-related pathology among males. The development of the Muscularity-Oriented Eating Test (MOET) represents an important advancement in ED assessment, enabling valid and reliable assessment of muscularity-oriented ED pathology among men. The current study sought to provide initial validity of the MOET among gay men. N = 264 gay men, recruited via MTurk, participated in a brief online survey, completing the MOET and other well-validated measures of eating pathology and body image psychopathology. Factor structure, mean, standard deviation, and intercorrelation between measures were assessed. The MOET demonstrated adequate factor structure, similar to that reported in the initial validation sample, and was significantly correlated with other measures of eating and body image psychopathology. The current study suggests initial validity of the MOET for use among gay men. Future research is needed among younger and more diverse samples of SM men, along with evidence of adequate test-retest reliability and absence of differential item functioning among gay men.