Suicide is a leading cause of global mortality. Suicide clusters have recently been identified among peer networks in high-income countries. This study investigates dynamics of suicide clustering within social networks of young Kenya men (n  = 532; 18-34 years). We found a strong, statistically significant association between reported number of friends who previously attempted suicide and present suicide ideation (odds ratio = 1.9; 95% confidence interval (1.42, 2.54); p  < 0.001). This association was mediated by lower collective self-esteem (23% of total effect). Meaning in life further mediated the association between collective self-esteem and suicide ideation. Survivors of peer suicide should be evaluated for suicide risk.