Eating disorders (EDs) are more common among younger women compared to older women and in women compared to men. As such, most ED research focuses on late adolescent and young adult females resulting in limited prospective research on gender differences in eating disorder psychopathology across the life span. The present study addresses this gap by examining gender differences in ED diagnoses, eating pathology, and the impact of putative risk factors on eating pathology in women (n = 624) and men (n = 276) over a 30-year period from late adolescence (M (SD) = 20[2] years) to later midlife (M (SD) = 50[2] years). Four assessment waves were conducted, beginning with baseline participation during college and subsequent 10-, 20-, and 30-year follow-up. Retention at 30-year follow-up was 72% (n = 440) for women and 67% (n = 181) for men. Prevalence of DSM-5 ED diagnoses decreased over the 30-year span for women and remained stable for men, with no significant gender difference in point prevalence by age 50. Drive for thinness decreased for women through age 50 and increased for men, while bulimic symptoms decreased as both genders aged. Multilevel models demonstrated that the impact of dieting as a risk factor on drive for thinness decreased prospectively as men aged and remained stable as women aged. Results imply that current risk models require refinement to account for developmental trajectories in which dramatic gender differences observed in late adolescence diminish over time. (PsycInfo Database Record (c) 2020 APA, all rights reserved).