Long-acting injectable pre-exposure prophylaxis for HIV prevention (LAI-PrEP) was approved for use in the United States in 2021, yet little is known about perceptions of LAI-PrEP among transgender and nonbinary young adults, a group that faces substantial barriers to HIV prevention. We investigated US transgender and nonbinary young adults' perceptions of and attitudes toward LAI-PrEP and how perceived advantages and disadvantages of LAI-PrEP related to the PrEP continuum of care. We conducted semi-structured interviews with 31 transgender and nonbinary young adults who reported oral PrEP use or were PrEP-eligible. We analyzed responses using both a deductive RADaR approach, to identify LAI-PrEP perceptions relevant to the PrEP continuum of care, and an inductive thematic analysis to explore key themes. In this study, all PrEP-experienced and most PrEP-naïve participants indicated an interest in LAI-PrEP, citing advantages over daily oral medication (e.g., fewer adherence challenges). Three key themes emerged: (1) Some participants linked perceived advantages of LAI-PrEP to experiences with gender-affirming care (e.g., familiarity with needles via hormone use). (2) Participants weighed trade-offs and contextual factors that influenced their LAI-PrEP preferences (e.g., interest contingent on whether location for receiving injection was geographically accessible). (3) Participants envisaged alternative delivery methods that could enhance LAI-PrEP acceptability and uptake (e.g., home injection). HIV prevention programs should incorporate the insights of transgender and nonbinary young adults to ensure that emerging HIV prevention technologies are accessible and responsive to the needs and concerns of people of all gender modalities.