Temporospatial patterns of temperature and precipitation are changing rapidly in arctic ecosystems, but the long-term effects of these changes on species interactions and energy flow are poorly understood. I sought to provide baseline data for understanding the effects of climate change by evaluating the diets of two avian apex predators in Alaska, the Golden Eagle (Aquila chrysaetos) and Gyrfalcon (Falco rusticolus). Specifically, I focused on (1) identifying the primary prey species and dietary breadth of Golden Eagles, (2) comparing the diets of Golden Eagles at successful and unsuccessful nest sites, and (3) comparing the diet of sympatric Golden Eagles and Gyrfalcons on the Seward Peninsula. I hypothesized that diets would vary between successful and unsuccessful nests of Golden Eagles due to energy requirements of young. Additionally, I predicted that while diets of Golden Eagles and Gyrfalcons would overlap, significant partitioning would occur among prey taxa that were common in both diets, consistent with niche theory and specialization. I estimated composition of Golden Eagle diet by analysis of regurgitated pellets and prey remains collected at 32 occupied nest sites (11 successful) in July 2014, and Gyrfalcon diet was estimated by direct observation at 10 successful nest sites May-July 2014. I found that the diets of both raptors consisted primarily of arctic ground squirrel (Urocitellus parryii) and ptarmigan (Lagopus spp.), but the relative proportions of these prey were reversed, with Golden Eagles preying more on squirrel (57% vs. 15% for Gyrfalcons), and Gyrfalcons preying more on ptarmigan (78% vs. 15% for Golden Eagles). The diets of Golden Eagles occupying successful and unsuccessful nests may vary but overlapped in composition by 99%. The breadth of Golden Eagle diet was significantly greater than that of Gyrfalcons, yet their diets overlapped in composition by 45% and was significantly different. These results help illuminate the shared niche space of and competition for prey between Golden Eagles and Gyrfalcons and, potentially, variation between these predators’ abilities to adapt to the effects of climate change, as changes in ptarmigan distribution and abundance are expected in Alaska. Additionally, these data help provide a baseline for future study of the effects of climate change on inter- and intratrophic interactions in arctic ecosystems.