IntroductionEvidence on the willingness of men who have sex with men (MSM) with oral pre-exposure prophylaxis (PrEP) experience, especially those with suboptimal adherence, to take long-acting injectable PrEP (LAI-PrEP) is critical to guide future LAI-PrEP implementation.ObjectiveThe objective was to assess the willingness of MSM with oral PrEP experience to take LAI-PrEP.MethodsMSM who participated in the China Real-world Study of Oral PrEP (CROPrEP) were enrolled in this study. Information on the willingness of MSM to take LAI-PrEP and potential correlates was collected using a structured online questionnaire. The main outcomes were the willingness of MSM to take LAI-PrEP and its association with HIV-related behaviours, sexually transmitted infections, and oral PrEP history. Logistic regression was used to identify correlates of the willingness of MSM to take LAI-PrEP.ResultsA total of 612 former CROPrEP participants (FCPs) were included in this study. There were 315 (51.5%) daily oral PrEP (D-PrEP) users and 297 (48.5%) event-driven oral PrEP (ED-PrEP) users at the last follow-up. Most FCPs (77.8%) were willing to take free LAI-PrEP. FCPs with no less than two sexual male partners (aOR = 1.54, [95% CI: 1.04, 2.29], P = 0.031), those with male partners with unknown HIV statuses (aOR = 2.04, [95% CI: 1.31, 3.18], P = 0.002), those with recreational drug use (aOR = 1.58, [95% CI: 1.05, 2.40], P = 0.030), and those with HSV-2 positivity (aOR = 2.15, [95% CI: 1.30, 3.57], P = 0.003) were more willing to take LAI-PrEP, while ED-PrEP users (aOR = 0.66, [95% CI: 0.45, 0.98], P = 0.037) and FCPs with suboptimal oral PrEP adherence (aOR = 0.58, [95% CI: 0.36, 0.94], P = 0.026) were less willing to take LAI-PrEP.ConclusionLAI-PrEP has good prospects for expanding PrEP coverage. However, FCPs with suboptimal oral PrEP adherence are less likely to take LAI-PrEP. Further intervention and implementation efforts are needed to improve the willingness of MSM to use LAI-PrEP, and sexual health should be considered during the discussion about PrEP initiation.