Pre-exposure prophylaxis (PrEP) has proven to be a powerful tool in preventing HIV infection. There is limited information about the factors associated with willingness to use different PrEP modalities among adolescent girls and young women (AGYW) in Africa. We assessed willingness to use long-acting injectable PrEP (LAI-PrEP) among 14-24-year-old AGYW at high risk of HIV in Uganda, and associated factors determined using multivariable complementary log-log regression. Of the 285 participants, 69.8% of participants showed willingness to use LAI-PrEP despite only 3.9% having knowledge about it before enrolment. Report of recent transactional sex was high (92.6%). Participants that were divorced/separated (aOR = 1.74, 95% CI 1.03-2.92) and those with multiple sexual partners (aOR = 2.11, 95% CI 1.46-3.06) compared to those with one partner were more likely to be willing to use LAI-PrEP while those that were screened as heavy episodic drinkers (consuming 6 or more drinks on an occasion as per the AUDIT tool) were less likely to be willing to use LAI-PrEP (aOR = 0.61, 95% CI 0.42-0.87). LAI PrEP has shown efficacy in clinical trials; the product is approved for use by the Government of Uganda (MoH) and should be expedited for use by AGYW engaged in paid sex and those with multiple sexual partnerships. As it becomes available, we recommend PrEP education and counseling to increase awareness of LAI PrEP as an alternative HIV prevention method.