BACKGROUND: A gonococcal vaccine is urgently needed due to increasing gonorrhoea incidence and emerging multidrug-resistant gonococcal strains worldwide. Men who have sex with men (MSM) have among the highest incidences of gonorrhoea and may be a key target population for vaccination when available. METHODS: An individual-based, anatomical site-specific mathematical model was used to simulate Neisseria gonorrhoeae transmission in a population of 10,000 MSM. The impact of vaccination on gonorrhoea prevalence was assessed. RESULTS: With a gonococcal vaccine of 100% or 50% protective efficacy, gonorrhoea prevalence could be reduced by 94% or 62%, respectively, within 2 years if 30% of MSM are vaccinated on presentation for STI testing. Elimination of gonorrhoea is possible within 8 years with vaccines of ≥50% efficacy over 2 years, providing a booster vaccination is available every 3 years on average. A vaccine's impact may be reduced if it is not effective at all anatomical sites. CONCLUSIONS: Our study indicates that with a vaccine of modest efficacy and an immunisation strategy that targets MSM presenting for STI screening, the prevalence of gonorrhoea in this population could be rapidly and substantially reduced.