BACKGROUND: Young men who have sex with men (MSM) are a key population at high risk of sexually transmitted infections (STIs). We conducted a respondent-driven sampling (RDS) bio-behavioural survey to estimate the prevalence of five curable STIs: chlamydia, gonorrhoea, syphilis, trichomoniasis and Mycoplasma genitalium infection, and associated risk factors among tertiary student MSM (TSMSM) in Nairobi, Kenya. METHODS: Between February and March 2021, we recruited 248 TSMSM aged ≥18years who self-reported engaging in anal and/or oral sex with another man in the past year. Samples collected included urine, anorectal and oropharyngeal swabs for pooled Chlamydia trachomatis , Mycoplasma genitalium , Neisseria gonorrhoeae and Trichomonas vaginalis testing using multiplex nucleic acid amplification tests, and venous blood for serological Treponema pallidum screening and confirmation of current infection. Participants self-completed a behavioural survey on a REDCap digital platform. Data analysis was done using RDS-Analyst (v0.72) and Stata (v15). Differences in proportions were examined using the chi-squared (χ 2 ) test, and unweighted multivariate logistic regression was used to assess factors associated with STI prevalence. RESULTS: RDS-adjusted prevalence rates of at least one of the five STIs, chlamydia, gonorrhoea, Mycoplasma genitalium infection, trichomoniasis and latent syphilis were 58.8%, 51.0%, 11.3%, 6.0%, 1.5% and 0.7%, respectively. Factors independently associated with STI prevalence were inconsistent condom use (adjusted odds ratio (AOR)=1.89, 95% confidence interval (CI): 1.03-3.47, P =0.038) and the last sex partner being a regular partner (AOR=2.35, 95% CI: 1.12-4.92, P =0.023). CONCLUSION: STI prevalence among TSMSM in Nairobi, Kenya, is disturbingly high, demonstrating urgent need for tailored testing, treatment and prevention interventions for this population.