Short-eared Owls (Asio flammeus) are a globally distributed species, but whether their breeding ecology varies biogeographically is unknown and results in a lack of regionally relevant knowledge to inform conservation needs. We investigated the breeding ecology of Hawaiian Short-eared Owls (A.f. sandwichensis), or Pueo, using data from both focal study sites and incidental observations across the state of Hawai‘i. At focal sites, we found that greater visual obstruction readings were top predictors of the use of a site for Pueo nesting. However, these same metrics did not necessarily translate to increased nest survival; nests initiated earlier in the season and with higher percent vegetation cover had higher daily nest survival rates. Breeding Pueo diet at focal study sites included a variety of rodent, bird, and insect species, but diet composition did not vary significantly among nests. Across both focal and incidental state-wide observations, we found that Pueo nesting season spans from November through July, and breeding habitats ranged from coastal vegetation on nearby atolls to high elevation native wet forest. This study is the first to describe Pueo breeding ecology, providing a baseline for management actions in Hawai‘i and filling a geographical knowledge gap for this widely distributed species.