Understanding nest site selection is critical to developing effective conservation management actions. The Superb Lyrebird (Menura novaehollandiae) is one of many endemic species extensively impacted by Australia’s unprecedented 2019–2020 megafires. Over a period of 5 months, an estimated 43% of the entire range of this slow-breeding species was burnt, with the biggest impact on the central subspecies M. n. novaehollandiae (55%). Four months prior to these megafires, we conducted a field study of nest site habitat selection in the Superb Lyrebird within the Greater Blue Mountains World Heritage Area (15,400 km 2): a key stronghold of the central subspecies of the Superb Lyrebird. We found that at the local scale, lyrebird nest sites were more likely to be found in habitats characterized by dense canopy trees and rich in rainforest elements such as vines and treeferns. At the landscape scale, lyrebird nests were most likely to be constructed in rainforest; this fire-sensitive habitat type made up only 1% of the Greater Blue Mountains World Heritage Area. The probability of nest occurrence also increased with slope. We also found that >74% of all nesting habitat within the Greater Blue Mountains World Heritage Area burned in the 2019–2020 megafires, including 80% of areas of high suitability for nesting. These results suggest that the impact of these megafires on Superb Lyrebirds may be greater than currently thought. Given the importance of rainforest as nesting habitat for the superb lyrebird, managers should prioritize its restoration and protect it from future fire events. More broadly, our results illustrate how large-scale catastrophic events—such as megafires—can disproportionately affect habitats critical to specific points within an organism’s life cycle.